
Consider the problem of minimizing the sum of two convex functions, one being smooth and the other non-smooth in Banach space. In this paper, we introduce a non-traditional forward-backward splitting method for solving such minimization problem. We establish different convergence estimates under different stepsize assumptions.
Citation: Weibo Guan, Wen Song. Convergence rates of the modified forward reflected backward splitting algorithm in Banach spaces[J]. AIMS Mathematics, 2023, 8(5): 12195-12216. doi: 10.3934/math.2023615
[1] | Cuiying Li, Rui Wu, Ranzhuo Ma . Existence of solutions for Caputo fractional iterative equations under several boundary value conditions. AIMS Mathematics, 2023, 8(1): 317-339. doi: 10.3934/math.2023015 |
[2] | Ahmed Alsaedi, Fawziah M. Alotaibi, Bashir Ahmad . Analysis of nonlinear coupled Caputo fractional differential equations with boundary conditions in terms of sum and difference of the governing functions. AIMS Mathematics, 2022, 7(5): 8314-8329. doi: 10.3934/math.2022463 |
[3] | Murat A. Sultanov, Vladimir E. Misilov, Makhmud A. Sadybekov . Numerical method for solving the subdiffusion differential equation with nonlocal boundary conditions. AIMS Mathematics, 2024, 9(12): 36385-36404. doi: 10.3934/math.20241726 |
[4] | Naimi Abdellouahab, Keltum Bouhali, Loay Alkhalifa, Khaled Zennir . Existence and stability analysis of a problem of the Caputo fractional derivative with mixed conditions. AIMS Mathematics, 2025, 10(3): 6805-6826. doi: 10.3934/math.2025312 |
[5] | Xinwei Su, Shuqin Zhang, Lixin Zhang . Periodic boundary value problem involving sequential fractional derivatives in Banach space. AIMS Mathematics, 2020, 5(6): 7510-7530. doi: 10.3934/math.2020481 |
[6] | Ayub Samadi, Chaiyod Kamthorncharoen, Sotiris K. Ntouyas, Jessada Tariboon . Mixed Erdélyi-Kober and Caputo fractional differential equations with nonlocal non-separated boundary conditions. AIMS Mathematics, 2024, 9(11): 32904-32920. doi: 10.3934/math.20241574 |
[7] | Karim Guida, Lahcen Ibnelazyz, Khalid Hilal, Said Melliani . Existence and uniqueness results for sequential ψ-Hilfer fractional pantograph differential equations with mixed nonlocal boundary conditions. AIMS Mathematics, 2021, 6(8): 8239-8255. doi: 10.3934/math.2021477 |
[8] | Nichaphat Patanarapeelert, Thanin Sitthiwiratthame . On nonlocal fractional symmetric Hanh integral boundary value problems for fractional symmetric Hahn integrodifference equation. AIMS Mathematics, 2020, 5(4): 3556-3572. doi: 10.3934/math.2020231 |
[9] | Abdelkader Amara . Existence results for hybrid fractional differential equations with three-point boundary conditions. AIMS Mathematics, 2020, 5(2): 1074-1088. doi: 10.3934/math.2020075 |
[10] | Yige Zhao, Yibing Sun, Zhi Liu, Yilin Wang . Solvability for boundary value problems of nonlinear fractional differential equations with mixed perturbations of the second type. AIMS Mathematics, 2020, 5(1): 557-567. doi: 10.3934/math.2020037 |
Consider the problem of minimizing the sum of two convex functions, one being smooth and the other non-smooth in Banach space. In this paper, we introduce a non-traditional forward-backward splitting method for solving such minimization problem. We establish different convergence estimates under different stepsize assumptions.
In graph theory, graph labeling is an assignment of labels or weights to the vertices and edges of a graph. Graph labeling plays an important role in many fields such as computer science, coding theory and physics [32]. Baca et al. [10] have introduced the definition of an edge irregular total ℓ-labeling of any graph as a labeling L:V∪E→{1,2,3,…,ℓ} in which every two distinct edges fh and f∗h∗ of a graph G have distinct weights, this means that wL(fh)≠wL(f∗h∗) where wL(fh)=L(f)+L(h)+L(fh). They have deduced inequality which gives a lower bound of tes(G) for a graph G,
tes(G)≥max{⌈|E(G)|+23⌉,⌈Δ+12⌉} | (1) |
Also, they have introduced the exact value of TEIS, tes(G) for some families of graphs like fan graph Fn and wheel graph Wn,
tes(Fn)=⌈3n+23⌉, |
tes(Wn)=⌈2n+23⌉. |
In [15] authors have proved that for any tree T
tes(T)=max{⌈k+13⌉,⌈Δ+12⌉}, |
where Δ is maximum degree on k vertices. In addition, Salama [26] investigated the exact value of TEIS for a polar grid graph,
tes(Pm,n)=⌈2mn+23⌉. |
Authors in [1] determined TEIS for zigzag graphs. Also, the exact value of TEIS of the generalized web graph Wn,m and some families has been determined, see [14]. Tilukay et al. [31] have investigated total irregularity strength for a wheel graph, a fan graph, a triangular Book graph and a friendship graph. On the other hand, in [2,3,8,17,20,24,29] the total edge irregularity strengths for hexagonal grid graphs, centralized uniform theta graphs, generalized helm graph, series parallel graphs, disjoint union of isomorphic copies of generalized Petersen graph, disjoint union of wheel graphs, subdivision of star Sn and categorical product of two cycles have been investigated. For more details, see [4,5,6,7,9,11,12,13,16,18,19,21,23,25,27,28,30].
A generalized theta graph θ(t1,t2,…,tn) is a pair of n internal disjoint paths with lengths at least two joined by end vertices where the end vertices are named south pole S and north pole N and ti is the number of vertices in the nth path. Uniform theta graph θ(t,m) is a generalized theta graph in which all paths have the same numbers of internal vertices, for more details see [22].
In this paper, we have defined a new type of family of graph called uniform theta snake graph, θn(t,m). Also, the exact value of TEIS for some special types of the new family has been determined.
In the following, we define a new type of graph which is called uniform theta snake graph.
Definition 1. If we replace each edge of a path Pn by a uniform theta graph θ(t,m), we have a uniform theta snake graph θn(t,m). See Figure 1.
It is clear that for a uniform theta snake graph |E(θn(t,m))|=t(m+1)n and |V(θn(t,m))|=(tm+1)n+1. In this section, we determine the exact value of TEIS for uniform theta snake graph θn(3,3), θn(3,m), θn(t,3), θn(4,m), and θn(t,4).
Theorem 1. For a uniform theta snake graph θn(3,3) with 10n+1 vertices and 12n edges, we have
tes(θn(3,3))=4n+1. |
Proof. Since a uniform theta snake graph θn(3,3) has 12n edges and (θn(3,3))=6, then from (1) we have:
tes(θn(3,3))≥4n+1. |
To prove the invers inequality, we show that ħ− labeling is an edge irregular total for θn(3,3), see Figure 2, and ħ=4n+1. Let ħ=4n+1 and a total ħ− labeling α:V(θn(3,3))∪E(θn(3,3))→{1,2,3,…,ħ} is defined as:
α(c0)=1, |
α(cs)=4sfor1≤s≤n−1 |
α(cn)=ħ, |
α(xi,j)={jfor1≤j≤3j+1for4≤j≤6....j+n−1for3n−2≤j≤3n−1,i=1,2,3, |
α(xi,3n)=ħ−1fori=1,2,3 |
α(c0xi,1)=ifori=i1,2,3 |
α(cSxi,3S)=4S+ifor1≤S≤n−1,i=1,2,3 |
α(cSxi,3S+1)=4S+i+1for1≤S≤n−1,i=1,2,3 |
α(cnxi,3n)={ħ−2fori=1ħ−1fori=2ħfori=3, |
α(xi,jxi,j+1i)={j+i+1for1≤j≤2j+i+2for4≤j≤5....j+i+n−I1for3n−5≤j≤3n−4ħ+i−3for3n−2≤j≤3n−1,i=1,2,3. |
It is clear that ħ is the greatest used label. The weights of edges of θn(3,3) are given by:
wα(c0xi,1)=i+2fori=1,2,3, |
wα(cSxi,3S)=12S+i−1for1≤S≤n−1,i=1,2,3 |
wα(cSxi,3S+1)=12S+i+2for1≤S≤n−1,i=1,2,3, |
wα(cnxi,3n)={3(ħ−1)fori=13ħ−2fori=23ħ−1fori=3, |
wα(xi,jxi,j+1)={3j+i+2for1≤j≤23j+i+5for4≤j≤5....3j+i+3n−4for3n−5≤j≤3n−43ħ+i−10forj=3n−23ħ+i−7forj=3n−1,i=1,2,3 |
Obviously, the weights of edges are distinct. So α is an edge irregular total ħ− labeling. Hence
tes(θn(3,3))=4n+1. |
Theorem 2. For θn(3,m),m>3 be a uniform theta snake graph. Then
tes(θn(3,m))=(m+1)n+1. |
Proof. Since |E(θn(3,m))|=3(m+1)n and Δ(θn(3,m))=6. Substituting in (1), we find
tes(θn(3,m))≥(m+1)n+1. |
The existence of an edge irregular total ƛ− labeling for θn(3,m), See Figure 3, m>3 will be shown, with ƛ=(m+1)n+1. Define a total ƛ− labeling β:V(θn(3,m))∪E(θn(3,m))→{1,2,3,…,ƛ} for θn(3,m) as:
β(c0)=1, |
β(cs)=(m+1)sfor1≤s≤n−1, |
β(cn)=ƛ |
β(xi,j)={jfor1≤j≤mj+1form+1≤j≤2m....j+n−1form(n−1)+1≤j≤mn−1, |
β(xi,mn)=ƛ−1fori=1,2,3 |
β(c0xi,1)=1fori=1,2,3 |
β(cSxi,mS)=(m+1)S+ifor1≤S≤n−1,i=1,2,3 |
β(cSxi,mS+1)=(m+1)S+i+1for1≤S≤n−1,i=1,2,3 |
β(cnxi,mn)={ƛ−2fori=1ƛ−1fori=2ƛfori=3, |
β(xi,jxi,j+1)={j+i+1for1≤j≤m−1j+i+2form+1≤j≤2m−1....j+i+nform(n−1)+1≤j≤mn−2j+i+n−1forj=mn−1. |
Clearly, ƛ is the most label of edges and vertices. The edges weights are given as follows:
wβ(c0xi,1)=i+2fori=1,2,3, |
wβ(cSxi,mS)=3(m+1)S+i−1for1≤S≤n−1,i=1,2,3 |
wβ(cSxi,mS+1)=3(m+1)S+i+2for1≤S≤n−1,i=1,2,3, |
wβ(cnxi,mn)={3ƛ−3fori=13ƛ−2fori=23ƛ−1fori=3, |
wβ(xi,jxi,j+1)={3j+i+2for1≤j≤m−13j+i+5form+1≤j≤2m−1....3jI+i+3n−1form(n−1)+1≤j≤mn−23ƛ+i−7forj=mn−1, |
It is obvious that the weights of edges are different, thus β is an edge irregular total ƛ− labeling of θn(3,m). Hence
tes(θn(3,m))=(m+1)n+1. |
Theorem 3. Let θn(t,3) be a theta snake graph for t>3. Then
tes(θn(t,3))=⌈4tn+23⌉. |
Proof. A size of the graph θn(t,3) equals 4tn and Δ(θn(t,3))=2t, then from (1) we have
tes(θn(t,3))≥⌈4tn+23⌉. |
We define an edge irregular total ħ− labeling for θn(t,3) to get upper bound. So, let ħ=⌈4tn+23⌉ and a total ħ− labeling γ:V(θn(t,3))∪E(θn(t,3))→{1,2,3,…,ħ} is defined in the following three cases:
Case 1. 4tn+2≡0(mod3)
γ is defined as:
γ(c0)=1, |
γ(cS)=(t+1)Sfor1≤S≤n−1, |
γ(cn)=ħ |
γ(xi,j)I={ifor1≤j≤3,i=1,2,…,ti+t+1for4≤j≤6,i=1,2,…,ti+2(t+1)for7≤j≤9,i=1,2,…,t......i+(n−1)(t+1)for3n−5≤j≤3n−3,i=1,2,…,tħ−1for3n−2≤j≤3n,i=1ħfor3n−2≤j≤3n,i=2,3,…,t, |
γ(c0xi,1)=1fori=1,2,…,t |
γ(cSxi,3S)=2St−2S+3for1≤S≤n−1,i=1,2,…,t |
γ(cnxi,3n)={ħ−t+2fori=1ħ−t+ifori=2,3,…,t, |
γ(cSxi,3S+1)=2St−2S+2for1≤S≤n−1,i=1,2,…,t |
γ(cn−1xi,3n−2)={{(t+2)n−t−5fori=1(t+2)n−t+i−7fori=2,3,…,t,n=2,3{(t+1)n−t−1fori=1(t+1)n−t+i−3fori=2,3,…,t,n≠2,3 |
γ(xi,jxi,j+1)={{t+jfor1≤j≤23t+j−5for4≤j≤55t+j−10for7≤j≤8......(2n−3)t+j−5(n−2)for3n−5≤j≤3n−4,i=1,2,…,tħ−3(t+n)+j+5for3n−2≤j≤3n−1,i=1ħ−3(t+n)+j+5+2(i−2)for3n−2≤j≤3n−1,i=2,3,…,t |
Obviously, ħ is the greatest label. The edges weights of θn(t,3) can be expressed as:
wγ(c0xi,1)=i+2fori=1,2,…,t |
wγ(cSxi,3S)=t(4S−1)+i+2for1≤S≤n−1,i=1,2,…,t |
wγ(cSxi,3S+1)=4St+i+2for1≤S≤n−1,i=1,2,…,t, |
wγ(cn−1xi,3n−2)={2nt+3n−2t+ħ+i−8forn=2,32nt+2n−2t+ħ+i−4forn≠2,3,i=1,2,…,t |
wγ(xi,jxi,j+1)={{t+j+2ifor1≤j≤25t+j+2i−4for4≤j≤59t+j+2i−6for7≤j≤8......(4n−5)t+j+2i−3n+8for3ni−5≤j≤3n−4,i=1,2,…,t3ħ−3(t+in)+j+3for3n−2≤j≤3n−1,i=13ħ−3(t+in)+j+2i+3for3n−2≤j≤3n−1,i=2,3,…,t |
It implies that the edges weights have distinct values. So γ is the desired edge irregular total ħ− labeling, ħ=⌈4tn+23⌉. Hence
tes(θn(t,3))=⌈4tn+23⌉. |
Case 2. 4tn+2≡1(mod3)
Defineγ as:
γ(c0)=1, |
γ(cS)=(t+1)Sfor1≤S≤n−1, |
γ(cn)=ħ |
γ(xi,j)={ifor1≤j≤3,i=1,2,…,ti+t+1for4≤j≤6,i=1,2,…,ti+2(t+1)for7≤j≤9,i=1,2,…,t......i+(n+1)(t+1)for3n−5≤j≤3n−3,i=1,2,…,tħ−1for3n−2≤j≤3n,i=1ħfor3n−2≤j≤3n,i=2,3,…,t, |
γ(c0xi,1)=1fori=1,2,…,t |
γ(cSxi,3S)=2St−2S+3for1≤S≤n−1,i=1,2,…,t |
γ(cnxi,3n)={ħ−tfori=1ħ−t+i−2fori=2,3,…,t, |
γ(cSxi,3S+1)=2St−2S+2for1≤IS≤n−1,i=1,2,…t |
γ(cn−1xi3n−2)={{(t+2)n−t−5fori=1(t+2)n−t+i−7fori=2,3,…,t,n=2,3{(t+1)n−t−1fori=1(It+I1)n−t+i−3fori=2,3,…,t,n≠2,3 |
γ(xi,jxi,j+1)={{t+jfor1≤j≤23t+j−5for4≤j≤55t+j−10for7≤j≤8......(2n−3)t+j−5(n−2)for3n−5≤j≤3n−4,i=1,2,…,tħ−3(t+n)+j+3for3n−2≤j≤3n−1,i=1ħ−3(t+n)+j+2(i−2)for3n−2≤j≤3n−1,i=2,3,…,t |
It is clear that the greatest label is ħ. We define the weights of edges of θn(t,3) as:
wγ(c0xi,1)=i+2fori=1,2,…,t |
wγ(cSxi,3S)=t(4S−1)+i+2for1≤S≤n−1,i=1,2,…,twγ(cnxi,3n)=3ħ−t+i−2for1≤S≤n−1,i=1,2,…,t |
wγ(cSxi,3S+1)=4St+i+2for1≤S≤n−1,i=1,2,…,t, |
wγ(cn−1xi,3n−2)={2nt+3n−2t+ħ+i−8forn=2,32nt+2n−2t+ħ+i−4forn≠2,3,i=1,2,…,t |
wγ(xi,jxi,j+1)={{t+j+2ifor1≤j≤25t+j+2i−4for4≤j≤59t+j+2i−6for7≤j≤8......(4n−5)t+j+2i−3n+8for3n−5≤j≤3n−4,i=1,2,…,t3ħ−3(t+n)+j+1for3n−2≤j≤3n−1,i=13ħ−3(t+n)+j+2(i−2)for3n−2≤j≤3n−1,i=2,3,…,t |
It is obvious that the edges weights are different. Then
tes(θn(t,3))=⌈4tn+23⌉. |
Case 3. 4tn+2≡2(mod3)
γ is defined as follows:
γ(c0)=1, |
γ(cS)=(t+1)Sfor1≤S≤n−1, |
γ(cn)=ħ |
γ(xi,j)={ifor1≤j≤3,i=1,2,…,ti+t+1for4≤j≤6,i=1,2,…,ti+2(t+1)for7≤j≤9,i=1,2,…,t......i+(n−1)(t+1)for3n−5≤j≤3n−3,i=1,2,…,tħ−1for3n−2≤j≤3n,i=1ħfor3n−2≤j≤3n,i=2,3,…,t, |
γ(c0xi,1)=1fori=1,2,…,t |
γ(cSxi,3S)=2St−2S+3for1≤S≤n−1,i=1,2,…,t |
γ(cnxi,3n)={ħ−t+1fori=1ħ−t+i−1fori=2,3,…,t, |
γ(cSxi,3S+1)=2St−2S+2for1≤S≤n−2,i=1,2,…,t |
γ(cn−1xi,3n−2)={{(t+2)n−t−5fori=1(t+2)n−t+i−7fori=2,3,…,t,n=2,3{(t+1)n−t−1fori=1(t+1)n−t+i−3fori=2,3,…,t,n≠2,3 |
γ(xi,jxi,j+1)={{t+jfor1≤j≤23t+j−5for4≤j≤55t+j−10for7≤j≤8......(2n−3)t+j−5(n−2)for3n−5≤j≤3n−4,i=1,2,…tħ−3(t+i)+j+4for3n−2≤j≤3ni−1,i=1ħ−3(t+n)+j+2ifor3n−2≤j≤3n−1,i=2,3,…,t |
We can see that ħ is the greatest label. For edges weights of θn(t,3), we have
wγ(c0xi,1)=i+2fori=1,2,…,t |
wγ(c0xi,3S)=t(4S−1)+i+2for1≤S≤n−1,i=1,2,…,twγ(cnxi,3n)=3ħ−t+i−1for1≤S≤n−1,i=1,2,…,t |
wγ(cSxi,3S+1)=4St+i+2for1≤S≤n−1,i=1,2,…,t, |
wγ(cnxi,3n−2)={2nt−3n−2t+ħ+i−8forn=2,32nt+2n−2t+ħ+i−4forn≠2,3,i=1,2,…,t |
wγ(xi,jxi,j+1)={{t+j+2ifor1≤j≤25t+j+2i−4for4≤j≤59t+j+2i−6for7≤j≤8......(4n−5)t+j+2i−3n+8for3n−5≤j≤3n−4,i=1,2,…,t3ħ−3(t+n)+j+2for3n−2≤j≤3n−1,i=13ħ−3(t+n)+j+2ifor3n−2≤j≤3n−1,i=2,3,…,t |
It clears that the edges weights are i distinct. So γ is the desired edge irregular total ħ− labeling, ħ=⌈4tn+23⌉. Hence
tes(θn(t,3))=⌈4tn+23⌉. |
Theorem 4. For θn(4,m) be a theta snake graph for t>3. Then
tes(θn(4,m))=⌈4(m+1)n+23⌉. |
Proof. Since |E(θn(4,m))|=4(m+1)n and Δ(θn(4,m))=8, then from (1) we have
tes(θn(4,m))≥⌈4(m+1)n+23⌉. |
The existence of an edge irregular total ƛ− labeling for θn(4,m), m>3 will be shown, with ƛ=⌈4(m+1)n+23⌉. Define a total ƛ− labeling β:V(θn(4,m))∪E(θn(4,m))→{1,2,3,…,ƛ} for θn(4,m) in the following three cases as:
Case 1. 4(m+1)n+2≡0(mod3), i=1,2,3,4
β is defined as:
β(cs)={1fors=0(m+1)sfor1≤s≤⌈n2⌉ƛ+s−nfor⌈n2⌉≤s≤n, |
β(xi,j)={jfor1≤j≤mj+1form+1≤j≤2m....j+⌈n2⌉−1ƛ−j+22ƛform(⌈n2⌉−1)+1≤j≤m⌈n2⌉+1form⌈n2⌉+2≤j≤m(n−1)form(n−1)+1≤j≤mn−1, |
β(c0xi,1)=1fori=1,2,3,4 |
β(cSxi,mS)={2cS+i−1for1≤S≤⌈n2⌉−1cS+i−4(m+1)for⌈n2⌉≤s≤n−1ƛ−4+ifors=n,i=1,2,3,4 |
β(cSxi,mS+1)={2cS+i+1for1≤S≤⌈n2⌉,i=1,2,3,4cS+i−4(m+1)+2for⌈n2⌉+1≤s≤n−1 |
β(cnxi,mn)={ƛ−3fori=1ƛ−2fori=2ƛ−1ƛfori=3fori=4, |
β(xi,jxi,j+1)={j+i+1for1≤j≤m−1j+i+2form+1≤j≤2m−1....j+i+⌈n2⌉forj=m(⌈n2⌉−1)+12j+i−2[nm(⌈n2⌉−1)+1]form(⌈n2⌉−1)+2≤j≤mn−1. |
It is clear that ƛ is the greatest used label. The weights of edges of θn(4,m) are given by:
wβ(c0xi,1)=i+2fori=1,2,3,4, |
wβ(cSxi,mS)={2ms+s+2cS+i−1for1≤S≤⌈n2⌉−1,cS+i+ƛ+(s−4)(m+1)−n+⌈n2⌉−1for⌈n2⌉≤s≤n−13ƛ−4+i+s−nfors=n,i=1,2,3,4 |
wβ(cSxi,mS+1)={(2m+1)s+2cS+i+1for1≤S≤⌈n2⌉,2ƛ+s−n+cS+i−4(m+1)+2for⌈n2⌉≤s≤n−1i=1,2,3,4, |
wβ(cnxi,mn)={3ƛ+s−n−3fori=13ƛ+s−n−2fori=23ƛ+s−n−13ƛ+s−nfori=3fori=4, |
wβ(xi,jxi,j+1)={3j+i+2for1≤j≤m−13j+i+4form+1≤j≤2m−1....3j+i+3⌈n2⌉−1forj=m(⌈n2⌉−1)+14j+2ƛ+45+i−2[nm(⌈n2⌉−1)+1]2j+2ƛ+i−2[nm(⌈n2⌉−1)+1]form⌈n2⌉+2≤j≤m(n−1)form(n−1)+1≤j≤mn−1, |
It is obvious that the weights of edges are different, thus β is an edge irregular total ƛ− labeling of θn(4,m). Hence
tes(θn(4,m))=⌈4(m+1)n+23⌉. |
Case 2. 4(m+1)n+2≡1(mod3), i=1,2,3,4
β is defined as:
β(cs)={1fors=0(m+1)sfor1≤s≤⌈n2⌉ƛ+s−nfor⌈n2⌉≤s≤n, |
β(xi,j)={jfor1≤j≤mj+1form+1≤j≤2m....j+⌈n2⌉−1ƛ−j+22ƛform(⌈n2⌉−1)+1≤j≤m⌈n2⌉form⌈n2⌉+1≤j≤m(n−1)form(n−1)+1≤j≤mn−1, |
β(c0xi,1)=1fori=1,2,3,4 |
β(cSxi,mS)={2cS+i−1for1≤S≤⌈n2⌉−1,ƛ−7+ifors=⌈n2⌉cS+i−4m−2for⌈n2⌉+1≤s≤n−1ƛ−6+ifors=n,i=1,2,3,4 |
β(cSxi,mS+1)={2cS+i+1for1≤S≤⌈n2⌉cS+i−4mfor⌈n2⌉≤s≤n−1,i=1,2,3,4 |
β(cnxi,mn)={ƛ−5fori=1ƛ−4fori=2ƛ−3ƛ−2fori=3fori=4, |
β(xi,jxi,j+1)={j+i+1for1≤j≤m−1j+i+2form+1≤j≤2m−1....j+i+⌈n2⌉forj=m(⌈n2⌉−1)+12j+i−2[nm(⌈n2⌉−1)+1]form(⌈n2⌉−1)+2≤j≤mn−1. |
It is clear that ƛ is the greatest used label. The weights of edges of θn(4,m) are given by:
wβ(c0xi,1)=i+2fori=1,2,3,4, |
wβ(cSxi,mS)={2ms+s+2cS+i−1for1≤S≤⌈n2⌉−1,2ƛ−m⌈n2⌉+(m+1)s+i+15fors=⌈n2⌉cS+i+ƛ+(s−4)(m+1)−n+⌈n2⌉−1for⌈n2⌉≤s≤n−13ƛ−4+i+s−nfors=n |
wβ(cSxi,mS+1)={(2m+1)s+2cS+i+1for1≤S≤⌈n2⌉,i=1,2,3,42ƛ+s−n+cS+i−4mfor⌈n2⌉≤s≤n−1i=1,2,3,4, |
wβ(cnxi,mn)={3ƛ+s−n−5fori=13ƛ+s−n−4fori=23ƛ+s−n−33ƛ+s−n−2fori=3fori=4, |
wβ(xi,jxi,j+1)={3j+i+2for1≤j≤m−13j+i+4form+1≤j≤2m−1....3j+i+3⌈n2⌉−1forj=m(⌈n2⌉−1)+14j+2ƛ+45+i−2[nm(⌈n2⌉−1)+1]2j+2ƛ+i−2[nm(⌈n2⌉−1)+1]form⌈n2⌉+2≤j≤m(n−1)form(n−1)+1≤j≤mn−1, |
It is obvious that the weights of edges are different, thus β is an edge irregular total ƛ− labeling of θn(4,m). Hence
tes(θn(4,m))=⌈4(m+1)n+23⌉. |
Case 3. 4(m+1)n+2≡2(mod3), i=1,2,3,4
β is defined as:
β(cs)={1fors=0(m+1)sfor1≤s≤⌈n2⌉ƛ+s−nfor⌈n2⌉≤s≤n, |
β(xi,j)={jfor1≤j≤mj+1form+1≤j≤2m....j+⌈n2⌉−1ƛ−j+22ƛform(⌈n2⌉−2)+1≤j≤m(⌈n2⌉−1)form(⌈n2⌉−1)+1≤j≤m(n−1)form(n−1)+1≤j≤mn−1, |
β(c0xi,1)=1fori=1,2,3,4 |
β(cSxi,mS)={2cS+i−1for1≤S≤⌈n2⌉−1,i=1,2,3,4ƛ−7+ifors=⌈n2⌉cS+i−4m−2for⌈n2⌉+1≤s≤n−1ƛ−5+ifors=n |
β(cSxi,mS+1)={2cS+i+1for1≤S≤⌈n2⌉−1,i=1,2,3,4cS+1+ifors=⌈n2⌉cS+i−4m+1for⌈n2⌉+1≤s≤n−1 |
β(cnxi,mn)={ƛ−4fori=1ƛ−3fori=2ƛ−2ƛ−1fori=3fori=4, |
β(xi,jxi,j+1)={j+i+1for1≤j≤m−1j+i+2form+1≤j≤2m−1....j+i+⌈n2⌉forj=m(⌈n2⌉−1)+12j+i−2[nm(⌈n2⌉−1)+1]+1form(⌈n2⌉−1)+2≤j≤mn−1. |
It is clear that ƛ is the greatest used label. The weights of edges of θn(4,m) are given by:
wβ(c0xi,1)=i+2fori=1,2,3,4, |
wβ(cSxi,mS)={2ms+s+2cS+i−1for1≤S≤⌈n2⌉−1,2ƛ−m⌈n2⌉+(m+1)s+i+15fors=⌈n2⌉cS+i+ƛ+(s−4)(m+1)−n+⌈n2⌉−1for⌈n2⌉≤s≤n−13ƛ−3+i+s−nfors=n |
wβ(cSxi,mS+1)={(2m+1)s+2cS+i+1for1≤S≤⌈n2⌉,i=1,2,3,42ƛ+s−n+cS+i−4m+1for⌈n2⌉≤s≤n−1, |
wβ(cnxi,mn)={3ƛ+s−n−3fori=13ƛ+s−n−2fori=23ƛ+s−n−13ƛ+s−nfori=3fori=4, |
wβ(xi,jxi,j+1)={3j+i+2for1≤j≤m−13j+i+4form+1≤j≤2m−1....3j+i+3⌈n2⌉−1forj=m(⌈n2⌉−1)+14j+2ƛ+45+i−2[nm(⌈n2⌉−1)+1]2j+2ƛ+i−2[nm(⌈n2⌉−1)+1]form⌈n2⌉+2≤j≤m(n−1)form(n−1)+1≤j≤mn−1, |
It is obvious that the weights of edges are different, thus β is an edge irregular total ƛ− labeling of θn(4,m). Hence
tes(θn(4,m))=⌈4(m+1)n+23⌉ |
Theorem 5. If θn(t,4) is theta snake graph for t>3. Then
tes(θn(t,4))=⌈5tn+23⌉. |
Proof. Since |E(θn(t,4))|=5tn and Δ(θn(t,4))=2t. Substituting in (1), we have
tes(θn(t,4))≥⌈5tn+23⌉. |
We define an edge irregular total ħ− labeling for θn(t,4) to get upper bound. Let ħ=⌈5tn+23⌉ and a total ħ− labeling γ:V(θn(t,4))∪E(θn(t,4))→{1,2,3,…,ħ} is defined in the following three cases:
Case 1. 5tn+2≡0(mod3)
Defineγ as:
γ(c0)=1, |
γ(cS)=(t+1)Sfor1≤S≤n−1, |
γ(cn)=ħ |
γ(xi,j)={ifor1≤j≤4,i=1,2,…,ti+t+1for5≤j≤8,i=1,2,…,ti+2(t+1)for9≤j≤12,i=1,2,…,t......i+(n−1)(t+1)for4n−7≤j≤4n−4,i=1,2,…,tħ−1for4n−3≤j≤4n,i=1ħfor4n−3≤j≤4n,i=2,3,…,t, |
γ(c0xi,1)=1fori=1,2,…,t |
γ(cSxi,4S)=3St−2S+3for1≤S≤n−1,i=1,2,…,t |
γ(cnxi,4n)={ħ−t+2fori=1ħ−t+ifori=2,3,…,t, |
γ(cSxi,4S+1)=3St−2S+2for1≤S≤n−1,i=1,2,…,t |
γ(cn−1xi,4n−3)={{(t+2)n−t−5fori=1(t+2)n−t+i−7fori=2,3,…,t,n=2,3(t+1)n−t+i−3fori=2,3,…,t,n≠2,3 |
γ(xi,jxi,j+1)={{t+jfor1≤j≤23t+j−5for4≤j≤55t+j−10for7≤j≤8......(2n−3)t+j−5(n−2)for4n−5≤j≤4n−4,i=1,2,…,tħ−3(t+n)+j+5for4n−2≤j≤4n,i=1ħ−3(t+n)+j+5+2(i−2)for4n−2≤j≤4n,i=2,3,…,t |
It is clear that, ħ is the greatest label. The edges weights of θn(t,4) can be expressed as:
wγ(c0xi,1)=i+2fori=1,2,…,t |
wγ(cSxi,4S)=t(5S−1)+i+2for1≤S≤n−1,i=1,2,…,twγ(cnxi,4n)=3ħ−t+ifori=1,2,…,t |
wγ(cSxi,4S+1)=5St+i+2for1≤S≤n−1,i=1,2,…,t, |
wγ(cn−1xi,4n−2)={2nt+3n−2t+ħ+i−8forn=2,32nt+2n−2t+ħ+i−6forn≠2,3,i=1,2,…,t |
wγ(xi,jxi,j+1)={{t+j+2ifor1≤j≤25t+j+2i−4for4≤j≤59t+j+2i−6for7≤j≤8......(4n−5)t+j+2i−3n+8for4n−5≤j≤4n−4,i=1,2,…,t3ħ−3(t+n)+j+3for4n−2≤j≤4n−1,i=13ħ−3(t+n)+j+2i+3for4n−2≤j≤4n−1,i=2,3,…,t |
It implies that the edges weights have distinct values. So γ is the desired edge irregular total ħ− labeling, ħ=⌈5tn+23⌉. Hence
tes(θn(t,4))=⌈5tn+23⌉. |
Case 2. 5tn+2≡1(mod3)
Defineγ as:
γ(c0)=1, |
γ(cS)=(t+1)Sfor1≤S≤n−1, |
γ(cn)=ħ |
γ(xi,j)={ifor1≤j≤4,i=1,2,…,ti+t+1for5≤j≤8,i=1,2,…,ti+2(t+1)for9≤j≤12,i=1,2,…,t......i+(n+1)(t+1)for4n−7≤j≤4n−4,i=1,2,…,tħ−1for4n−3≤j≤4n,i=1ħfor4n−3≤j≤4n,i=2,3,…,t, |
γ(c0xi,1)=1fori=1,2,…,t |
γ(cSxi,4S)=3St−2S+3for1≤S≤n−1,i=1,2,…,t |
γ(cnxi,4n)={ħ−tfori=1ħ−t+i−2fori=2,3,…,t, |
γ(cSxi,4S+1)=3St−2S+2 |
for1≤S≤n−1,i=1,2,…t |
γ(cn−1xi,4n−3)={{(t+2)n−t−5fori=1(t+2)n−t+i−7fori=2,3,…,t,n=2,3{(t+1)n−t−1fori=1(t+1)n−t+i−3fori=2,3,…,t,n≠2,3 |
γ(xi,jxi,j+1)={{t+jfor1≤j≤33t+j−5for5≤j≤75t+j−10for9≤j≤11......(2n−3)t+j−5(n−2)for4n−7≤j≤4n−5,i=1,2,…,tħ−4(t+n)+j+3for4n−3≤j≤4n−1,i=1ħ−4(t+n)+j+2(i−2)for4n−3≤j≤4n−1,i=2,3,…,t |
It is clear that the i greatest label is ħ. We define the weights of edges of θn(t,4) as:
wγ(c0xi,1)=i+2fori=1,2,…,t |
wγ(cSxi,4S)=t(5S−1)+i+2for1≤S≤n−1,i=1,2,…,twγ(cnxi,4n)=3ħ−t+i−2for1≤S≤n−1,i=1,2,…,t |
wγ(cSxi,4S+1)=5St+i+2for1≤S≤n−1,i=1,2,…,t, |
wγ(cn−1xi,4n−3)={3nt+3n−2t+ħ+i−8forn=2,33nt+2n−2t+ħ+i−6forn≠2,3,i=1,2,…,t |
wγ(xi,jxi,j+1)={{t+j+2ifor1≤j≤35t+j+2i−4fori5≤j≤79t+j+2i−6for9≤j≤11......(4n−5)t+j+2i−3n+8for4n−7≤j≤4n−5,i=1,2,…,t3ħ−4(t+n)+j+1for4n−3≤j≤4n−1,i=13ħ−4(t+n)+j+2(i−2)for4n−3≤j≤4n−1,i=2,3,…,t |
It is obvious that the edges weights are different. Then
tes(θn(t,4))=⌈5tn+23⌉. |
Case 3. 5tn+2≡2(mod3)
Defineγ as:
γ(c0)=1, |
γ(cS)=(t+1)Sfor1≤S≤n−1, |
γ(cn)=ħ |
γ(xi,j)={ifor1≤j≤4,i=1,2,…,ti+t+1for5≤j≤8,i=1,2,…,ti+2(t+1)for9≤j≤12,i=1,2,…,t......i+(in−1)(t+1)for4n−7≤j≤4n−4,i=1,2,…,tħ−1for4n−3≤j≤4n,i=1ħfor4n−3≤j≤4n,i=2,3,…,t, |
γ(c0xi,1)=1fori=1,2,…,t |
γ(cSxi,4S)=3St−2S+3for1≤S≤n−1,i=1,2,…,t |
γ(cnxi,4n)={ħ−t+1fori=1ħ−t+i−1fori=2,3,…,t, |
γ(cSxi,4S+1)=3St−2S+2for1≤S≤n−2,i=1,2,…,t |
γ(cn−1xi,4n−3)={{(t+2)n−t−5fori=1(t+2)n−t+i−7fori=2,3,…,t,n=2,3{(t+1)n−t−1fori=1(t+1)n−t+i−3fori=2,3,…,t,n≠2,3 |
γ(xi,jxi,j+1)={{t+jfor1≤j≤33t+j−5for5≤j≤75t+j−10for9≤j≤11......(2n−3)t+j−5(n−2)for4n−7≤j≤4n−5,i=1,2,…tħ−4(t+n)+j+4for4n−3≤j≤4n−1,i=1ħ−4(t+n)+j+2ifor4n−3≤j≤4n−1,i=2,3,…,t |
We can see that ħ is the greatest label. For edges weights of θn(t,4), we have:
wγ(c0xi,1)=i+2fori=1,2,…,t |
wγ(c0xi,4S)=t(5S−1)+i+2for1≤S≤n−1,i=1,2,…,twγ(cnxi,4n)=3ħ−t+i−1for1≤S≤in−1,i=1,2,…,t |
wγ(cSxi,4S+1)=5St+i+2for1≤S≤n−1,i=1,2,…,t, |
wγ(cnxi,4n−3)={2nt−3n−2t+ħ+i−8forn=2,32nt+2n−2t+ħ+i−6forn≠2,3,i=1,2,…,t |
wγ(xi,jxi,j+1)={{t+j+2ifor1≤j≤35t+j+2i−4for5≤j≤79t+j+2i−6for9≤j≤11......(4n−5)t+j+2i−3n+8for4n−7≤j≤4n−5,i=1,2,…,t3ħ−4(t+n)+j+2for4n−3≤j≤3n−1,i=13ħ−4(t+n)+j+2ifor4n−3≤j≤4n−1,i=2,3,…,t |
It is obvious that the edges weights are distinct. So γ is the desired edge irregular total ħ− labeling, ħ=⌈5tn+23⌉. Hence
tes(θn(t,4))=⌈5tn+23⌉. |
The previous results lead us to introduce the following conjecture for a general case of a uniform theta snake graph θn(t,m).
The previous results lead us to introduce the following conjecture for a general case of a uniform theta snake graph θn(t,m).
Conjecture. For uniform theta snake graph θn(t,m), n≥2,t≥3,andm≥3 we have
tes(θn(t,m))=⌈(m+1)tn+23⌉. |
In the current paper, we have defined a new type of a family of graph called uniform theta snake graph, θn(t,m). Also, the exact i value of TEISs for θn(3,3), θn(3,m) and θn(t,3) has been determined. Finally, we have generalized for t, m and found TEIS of a uniform theta snake graph θn(t,m) for m≥3, t≥3.
tes(θn(3,3))=4n+1. |
tes(θn(3,im))=(im+1)in+1. |
tes(θn(t,3))=⌈4tn+23⌉ |
tes(θn(t,m))=⌈(m+1)tn+23⌉. |
All authors declare no conflict of interest in this paper.
We are so grateful to the reviewer for his many valuable suggestions and comments that significantly improved the paper.
[1] |
P. L. Combettes, D. Dũng, B. C. Vũ, Dualization of signal recovery problems, Set-Valued Var. Anal., 18 (2010), 373–404. https://doi.org/10.1007/s11228-010-0147-7 doi: 10.1007/s11228-010-0147-7
![]() |
[2] |
P. L. Combettes, Inconsistent signal feasibility problems: least-squares solutions in a product space, IEEE Trans. Signal Process., 42 (1994), 2955–2966. https://doi.org/10.1109/78.330356 doi: 10.1109/78.330356
![]() |
[3] |
P. L. Combettes, V. R. Wajs, Signal recovery by proximal forward-backward splitting, Multiscale Model. Sim., 4 (2005), 1168–1200. https://doi.org/10.1137/050626090 doi: 10.1137/050626090
![]() |
[4] |
P. L. Lions, B. Mercier, Splitting algorithms for the sum of two nonlinear operators, SIAM J. Numer. Anal., 16 (1979), 964–979. https://doi.org/10.1137/0716071 doi: 10.1137/0716071
![]() |
[5] |
Y. Malitsky, M. K. Tam, A forward-backward splitting method for monotone inclusions without cocoercivity, SIAM J. Optim., 30 (2020), 1451–1472. https://doi.org/10.1137/18M1207260 doi: 10.1137/18M1207260
![]() |
[6] |
A. Padcharoen, D. Kitkuan, W. Kumam, P. Kumam, Tseng methods with inertial for solving inclusion problems and application to image deblurring and image recovery problems, Comput. Math. Methods, 3 (2021), 2577-7408 https://doi.org/10.1002/cmm4.1088 doi: 10.1002/cmm4.1088
![]() |
[7] |
K. Bredies, A forward-backward splitting algorithm for the minimization of nonsmooth convex functionals in Banach space, Inverse Probl., 25 (2008), 14228341. https://doi.org/10.1088/0266-5611/25/1/015005 doi: 10.1088/0266-5611/25/1/015005
![]() |
[8] |
W. B. Guan, W. Song, The generalized forward-backward splitting method for the minimization of the sum of two functions in Banach spaces, Numer. Func. Anal. Opt., 36 (2015), 867–886. https://doi.org/10.1080/01630563.2015.1037591 doi: 10.1080/01630563.2015.1037591
![]() |
[9] |
W. B. Guan, W. Song, The forward-backward splitting method and its convergence rate for the minimization of the sum of two functions in Banach space. Optim. Lett., 15 (2021), 1735–1758. https://doi.org/10.1007/s11590-020-01544-9 doi: 10.1007/s11590-020-01544-9
![]() |
[10] |
F. E. Browder, Fixed point therems for nonlinear semicontractive mappings in Banach spaces, Arch. Rational Mech. Anal., 21 (1966), 259–269. https://doi.org/10.1007/BF00282247 doi: 10.1007/BF00282247
![]() |
[11] |
J. P. Gossez, E. L. Dozo, Some geometric properties related to the fixed point theory for nonexpansive mappings, Pac. J. Math., 40 (1972), 565–573. https://doi.org/10.2140/PJM.1972.40.565 doi: 10.2140/PJM.1972.40.565
![]() |
[12] | I. Cioranescu, Geometry of Banach spaces, duality mappings and nonlinear problems, Dordrecht: Springer, 1990. |
[13] | W. Takahashi, Convex analysis and approximation of fixed points, Japan: Yokohama Publishers, 2000. |
[14] |
Y. I. Alber, R. S. Burachik, A. N. Iusem, A proximal point method for nonsmooth convex optimization problems in Banach spaces, Abstr. Appl. Anal., 2 (1996), 614871. https://doi.org/10.1155/S1085337597000298 doi: 10.1155/S1085337597000298
![]() |
[15] |
Y. I. Alber, Metric and generalized projection operators in Banach spaces: properties and applications, Mathematics, 1 (1993), 1109–1120. https://doi.org/10.48550/arXiv.funct-an/9311001 doi: 10.48550/arXiv.funct-an/9311001
![]() |
[16] | Y. I. Albert, I. Ryazantseva, Nonlinear ill-posed problems of monotone type, Dordrecht: Springer, 2006. https://doi.org/10.1007/1-4020-4396-1 |
[17] |
Y. Yao, N. Shahzad, Strong convergence of aproximal point algorithm with general errors, Optim. Lett., 6 (2012), 621–628. https://doi.org/10.1007/s11590-011-0286-2 doi: 10.1007/s11590-011-0286-2
![]() |
[18] | Y. I. Alber, S. Reich, D. Shoikhet, Iterative approximations of null points of uniformly accretive operators with estimates of convergence rate, Communications in Applied Analysis, 6 (2002), 89–104. |
[19] |
H. Attouch, M. O. Czarnecki, J. Peypouquet, Coupling forward-backward with penalty schemes and parallel splitting for constrained variational inequalities, SIAM J. Optim., 21 (2011), 1251–1274. https://doi.org/10.1137/110820300 doi: 10.1137/110820300
![]() |
[20] |
S. Kamimura, W. Takahashi, Strong convergence of a proximal type algorithm in a Banach space, SIAM J. Optim., 13 (2002), 938–945. https://doi.org/10.1137/S105262340139611X doi: 10.1137/S105262340139611X
![]() |
[21] |
S. Sabach, S. Shtern, A first order method for solving convex bilevel optimization problems, SIAM J. Optim., 27 (2017), 640–660. https://doi.org/10.1137/16M105592X doi: 10.1137/16M105592X
![]() |
[22] | D. P. Bertsekas, Nonlinear programming, 2 Eds., MA: Athena Scientific, 1999. |
[23] |
M. Bounkhel, R. Al-Yusof, Proximal analysis in reflexive smooth Banach spaces, Nonlinear Analysis, 73 (2010), 1921–1939. https://doi.org/10.1016/j.na.2010.04.077 doi: 10.1016/j.na.2010.04.077
![]() |