Processing math: 100%
Research article

Analysis of a prey-predator system incorporating the additive Allee effect and intraspecific cooperation

  • Received: 30 September 2023 Revised: 18 November 2023 Accepted: 26 November 2023 Published: 07 December 2023
  • MSC : 34C23, 34D23

  • To understand the influence of the Allee effect and intraspecific cooperation on the dynamics of a predator-prey system, we constructed a model using ordinary differential equations. Our research shows that the system exhibits more complex dynamics, including possible bistability between alternative semi-trivial states and an Allee effect for prey. The Allee effect can destabilize the system. The equilibrium points of the system could change from stable to unstable. Otherwise, even if the system were stable, it would take much longer time to reach a stable state. We also find that the presence of the Allee effect of prey increases the positive equilibrium density of the predator but has no effect on the positive equilibrium density of the prey. It should be noted that the influence of nonlinear predator mortality also causes the system to take a longer time to reach a steady state.

    Citation: Yalong Xue. Analysis of a prey-predator system incorporating the additive Allee effect and intraspecific cooperation[J]. AIMS Mathematics, 2024, 9(1): 1273-1290. doi: 10.3934/math.2024063

    Related Papers:

    [1] Jiankang Wang, Zhefeng Xu, Minmin Jia . Distribution of values of Hardy sums over Chebyshev polynomials. AIMS Mathematics, 2024, 9(2): 3788-3797. doi: 10.3934/math.2024186
    [2] Zhenjiang Pan, Zhengang Wu . The inverses of tails of the generalized Riemann zeta function within the range of integers. AIMS Mathematics, 2023, 8(12): 28558-28568. doi: 10.3934/math.20231461
    [3] Taekyun Kim, Dae San Kim, Dmitry V. Dolgy, Jongkyum Kwon . Sums of finite products of Chebyshev polynomials of two different types. AIMS Mathematics, 2021, 6(11): 12528-12542. doi: 10.3934/math.2021722
    [4] Utkal Keshari Dutta, Prasanta Kumar Ray . On the finite reciprocal sums of Fibonacci and Lucas polynomials. AIMS Mathematics, 2019, 4(6): 1569-1581. doi: 10.3934/math.2019.6.1569
    [5] S. Akansha, Aditya Subramaniam . Exploring Chebyshev polynomial approximations: Error estimates for functions of bounded variation. AIMS Mathematics, 2025, 10(4): 8688-8706. doi: 10.3934/math.2025398
    [6] Jin Li . Barycentric rational collocation method for semi-infinite domain problems. AIMS Mathematics, 2023, 8(4): 8756-8771. doi: 10.3934/math.2023439
    [7] Muhammad Uzair Awan, Nousheen Akhtar, Artion Kashuri, Muhammad Aslam Noor, Yu-Ming Chu . 2D approximately reciprocal ρ-convex functions and associated integral inequalities. AIMS Mathematics, 2020, 5(5): 4662-4680. doi: 10.3934/math.2020299
    [8] Tingting Du, Zhengang Wu . Some identities involving the bi-periodic Fibonacci and Lucas polynomials. AIMS Mathematics, 2023, 8(3): 5838-5846. doi: 10.3934/math.2023294
    [9] Xiao Jiang, Shaofang Hong . On the denseness of certain reciprocal power sums. AIMS Mathematics, 2019, 4(3): 412-419. doi: 10.3934/math.2019.3.412
    [10] Waleed Mohamed Abd-Elhameed, Omar Mazen Alqubori, Ahmed Gamal Atta . A collocation procedure for the numerical treatment of FitzHugh–Nagumo equation using a kind of Chebyshev polynomials. AIMS Mathematics, 2025, 10(1): 1201-1223. doi: 10.3934/math.2025057
  • To understand the influence of the Allee effect and intraspecific cooperation on the dynamics of a predator-prey system, we constructed a model using ordinary differential equations. Our research shows that the system exhibits more complex dynamics, including possible bistability between alternative semi-trivial states and an Allee effect for prey. The Allee effect can destabilize the system. The equilibrium points of the system could change from stable to unstable. Otherwise, even if the system were stable, it would take much longer time to reach a stable state. We also find that the presence of the Allee effect of prey increases the positive equilibrium density of the predator but has no effect on the positive equilibrium density of the prey. It should be noted that the influence of nonlinear predator mortality also causes the system to take a longer time to reach a steady state.



    The properties of orthogonal polynomials and recursive sequences are popular in number theory. They are important in theoretical research and application. The famous Chebyshev polynomials and Fibonacci polynomials are widely used in the field of function, approximation theory and difference equation. They also promote the development of both the branch of mathematics such as cryptography, combinatorics and application of discipline such as intelligent sensing, satellite positioning. Furthermore, they are close to the Fibonacci numbers and Lucas numbers. Therefore, a large number of scholars have investigated them and get many properties and identities.

    In the aspect of sums of reciprocals, Millin [1] originally studied the infinite sums of reciprocal Fibonacci series where the subscript is 2n. Based on the initial achievement, Good [2] further studied this issue and proved

    n=01F2n=752.

    Afterwards, Ohtsuka and Nakamura [3] deduced the infinite sum of reciprocal Fibonacci series

    (k=n1Fk)1={FnFn1,if n is even and n2 ,FnFn11,if n is odd and n1;

    and the infinite sum of reciprocal square Fibonacci series

    (k=n1F2k)1={FnFn11,if n is even and n2 ,FnFn1,if n is odd and n1;

    Similar properties were investigated in several different ways, see reference [4,5]. Falcón and Plaza [6,7,8] used Fibonacci polynomials to study Fibonacci numbers and get a lot of identities. For example,

    n1k=1Fk(x)Fnk(x)=(n1)xFn(x)+2nFn1(x)x2+4,
    nk=1Fk(x)=Fn+1(x)+Fn(x)1x

    where n and k are positive integers. This fact allows them to invest some integer sequences in a new and direct way. With these fundamental achievements, Wu and Zhang[9] proceeded generation and deduced the the infinite sum of reciprocal Fibonacci polynomials

    (k=n1Fk(x))1={Fn(x)Fn1(x),if n is even and n2 ,Fn(x)Fn1(x)1,if n is odd and n1;

    and the the infinite sum of reciprocal square Fibonacci polynomials

    (k=n1F2k(x))1={xFn(x)Fn1(x)1,if n is even and n2 ,xFn(x)Fn1(x),if n is odd and n1;

    where x is any positive integer. besides, Panda et al.[10] did some research about bounds for reciprocal sums in terms of balancing and Lucas-balancing sequences. Also, Dutta and Ray[11] found some identities about finite reciprocal sums of Fibonacci and Lucas polynomials.

    As we know, the first and the second kind of Chebyshev polynomials are usually defined as follows: Tn+2(x)=2xTn+1(x)Tn(x), n0, with the initial values T0(x)=1, T1(x)=x; Un+2(x)=2xUn+1(x)Un(x), n0, with the initial values U0(x)=1, U1(x)=2x; Then from the second-order linear recurrence sequences we have

    Tn(x)=12[(x+x21)n+(xx21)n],Un(x)=12x21[(x+x21)n+1(xx21)n+1].

    Based on these sequences, many scholars used these polynomials to study the Fibonacci sequences and the Lucas sequences and have investigated them and got many properties of Fn and Ln. For example, Zhang[12] used the Chebyshev polynomials and has obtain the general formulas involving Fn and Ln

    a1+a2++ak+1=nFm(a1+1)Fm(a2+1)Fm(ak+1+1)=(i)mnFk+1m2kk!U(k)n+k(imLm2).
    a1+a2++ak+1=n+k+1Lm(a1+1)Lm(a2+1)Lm(ak+1+1)
    =(i)m(n+k+1)2k!k+1h=0(im+2Lm2)h(k+1)!h!(k+1h)!U(k)n+2k+1h(imLm2),

    where k, m are any positive integers, a1, a2, ak+1 are nonnegative integers and i is the square root of 1. Wu and Yang[13] also studied Chebyshev polynomials and got a lot of properties. Besides, Dilcher and Stolarsky[14] established several related results involving resultants and discriminants about Chebyshev polynomials. Furthermore, bounds about the discriminant of the Chebyshev polynomials were given by Filipovski[15].

    A variety of sums about Chebyshev polynomials are hot issues in the number theory all the time. For example, Cesarano [16] gained several conclusions about the generating function of Chebyshev polynomials

    n=0ξnTn+l(x)=(1ξx)Tl(x)ξ(1x2)Ul112ξx+ξ2

    and the identical equation

    n=0ξnUn1+l(x)=ξTl(x)(1ξx)Ul112ξx+ξ2

    In this, ξ is a real number and 1<ξ<1. Furthermore, Knopfmacher et al.[17] did some research and got the result as follows:

    1Um(x)=1m+1mj=1(1)j+1sin2θjxcosθj

    and the identical equation

    1+Um1(x)Um(x)=1m+1mj=1[1+(1)j+1]sin2θjxcosθj,

    where θj=jπm+1, m is a positive integer.

    In this paper, we combine Ohtsuka and Falcón's ideas. Then we consider the subseries of infinite sums derived from the reciprocals of the Chebyshev polynomials and prove the following:

    Theorem 1. For any positive integer n, m and x, we have the following formula

    (k=n1Tmk(x))1=Tmn(x)Tmnm(x)

    Theorem 2. For any positive integer n, and x, we have the following formula

    (k=n1Uk(x))1=Un(x)Un1(x)1.

    Theorem 3. For any positive integer n, and x, we have the following formula

    (k=n1U2k(x))1=U2n(x)U2n1(x)1.

    With Falcón's enlightening, we can apply similar method into deduction of partial sums of Chebyshev polynomials. For convenient expression, we firstly set

    Gn(x)=Un1(x)Un(x)+Un1(x)Un+1(x)
    Mn(x)=Un2(x)Un(x)+Un1(x)Un(x)

    and obtain:

    Theorem 4. For any positive integer n,

    2n+1k=0k2Uk(x)=12(2n+1)U2n+1(x)Gn(x)+1+(n+1)U2n+2(x)+Mn(x).

    Theorem 5. For any positive integer n,

    2nk=0k2Tk(x)=12(2n+1)2U2n1(x)U2n(x)+2(n+1)2U2n+2(x)U2n+1(x).

    Theorem 6. For any positive integer n,

    2nk=0k3Tk(x)=4(n+1)3U2n+2(x)+12(2n+1)3U2n+1(x)Gn(x)(3n+32)U2n1(x)3nU2n(x)+3Mn(x)1.

    In order to prove the results of the infinite sums of reciprocal Chebyshev polynomials, several lemmas are needed.

    Let α=x+x21 and β=xx21, then we have the following lemmas.

    Lemma 1. For any positive integer n, we have

    U2n(x)=1+Un1(x)Un+1(x),
    U2n(x)=4x2+Un2(x)Un+2(x).

    Proof. From the definition of Chebyshev polynomials, we have

    U2n(x)Un1(x)Un+1(x)=(αn+1βn+1)2(αnβn)(αn+2βn+2)(αβ)2=α2n+2+β2n+2+α2+β22α2n+2β2n+2(αβ)2=1.U2n(x)Un2(x)Un+2(x)=(αn+1βn+1)2(αn1βn1)(αn+3βn+3)(αβ)2=α2n+2+β2n+2+α4+β42α2n+2β2n+2(αβ)2=(α+β)2=4x2.

    Lemma 2. For any positive integer n, we have

    T2n(x)=Tn1(x)Tn+1(x)+1x2,
    T2n(x)=Tn2(x)Tn+2(x)+4x2(1x2).

    Proof. From the definition of Chebyshev polynomials, we have

    T2n(x)Tn1(x)Tn+1(x)=14[(αn+βn)2(αn1+βn1)(αn+1+βn+1)]=14[α2+β22]=14(αβ)2=1x2.T2n(x)Tn2(x)Tn+2(x)=14[(αn+βn)2(αn2+βn2)(αn+2+βn+2)]=14[α2n+β2nα4β4+2α2nβ2n]=14(α+β)2(αβ)2=4x2(1x2).

    Lemma 3. For any positive integer n and m, we have

    Tn(Tm(x))=Tnm(x),
    Un(Tm(x))=Um(n+1)1(x)Um1(x).

    Proof. See Reference [12].

    Lemma 4. For any positive integer n and x, we have

    1Tn(x)+1Tn+1(x)<1Tn(x)Tn1(x)1Tn+2(x)Tn+1(x),1Tn(x)+1Tn+1(x)>1Tn(x)Tn1(x)+11Tn+2(x)Tn+1(x)+1.

    Proof. The first inequality equivalent to

    Tn(x)+Tn+1(x)Tn(x)Tn+1(x)<Tn+2(x)Tn+1(x)Tn(x)+Tn1(x)(Tn(x)Tn1(x))(Tn+2(x)Tn+1(x)), (2.1)

    or

    [Tn(x)+Tn+1(x)](Tn(x)Tn1(x)+1)(Tn+2(x)Tn+1(x)+1)<Tn(x)Tn+1(x)[Tn+2(x)Tn+1(x)Tn(x)+Tn1(x)],

    Then we have

    T2n(x)Tn+2(x)+T2n+1(x)Tn1(x)<Tn1(x)Tn+2(x)Tn(x)+Tn1(x)Tn+2(x)Tn+1(x),

    applying Lemma 2, inequality (2.1) is equivalent to

    (1x2)[Tn1(x)+Tn+2(x)]<0. (2.2)

    For any positive x and n1, 1x2<0 and Tn1(x)+Tn+2(x)>0. Thus it is very easy to check inequality (2.2) is true. Similarly, we can consider the second inequality of Lemma 4. The second inequality is equivalent to

    Tn(x)+Tn+1(x)Tn(x)Tn+1(x)>Tn+2(x)Tn+1(x)Tn(x)+Tn1(x)(Tn(x)Tn1(x)+1)(Tn+2(x)Tn+1(x)+1), (2.3)

    or

    T2n(x)Tn+2(x)Tn1(x)Tn(x)Tn+2(x)Tn1(x)Tn+1(x)Tn+2(x)+Tn(x)Tn+2(x)+Tn+1(x)Tn+2(x)+T2n+1(x)Tn1(x)T2n+1(x)+T2n(x)Tn(x)Tn1(x)Tn+1(x)Tn1(x)+Tn(x)+Tn+1(x)>0,

    applying Lemma 2, inequality (2.3) is equivalent to

    (Tn+1(x)(x21))Tn+2(x)(Tn(x)+(x21))Tn1(x)+Tn(x)+Tn+1(x)>0. (2.4)

    For any positive x and n1,

    (Tn+1(x)(x21))Tn+2(x)(Tn(x)+(x21))Tn1(x)>0

    Thus it is very easy to check inequality (2.4) is true.

    Lemma 5. For any positive integer n and x,

    1Un(x)+1Un+1(x)>1Un(x)Un1(x)1Un+2(x)Un+1(x),1Un(x)+1Un+1(x)<1Un(x)Un1(x)11Un+2(x)Un+1(x)1.

    Prove. The first inequality is equivalent to

    Un+1(x)+Un(x)Un+1(x)Un(x)>Un+2(x)Un+1(x)Un(x)+Un1(x)(Un(x)Un1(x))(Un+2(x)Un+1(x)), (2.5)

    or

    [Un+1(x)+Un(x)](Un(x)Un1(x))(Un+2(x)Un+1(x))>Un+1(x)Un(x)[Un+2(x)Un+1(x)Un(x)+Un1(x)],

    Then we have

    U2n(x)Un+2(x)+U2n+1(x)Un1(x)>Un(x)Un+2(x)Un1(x)+Un1(x)Un+1(x)Un+2(x),

    applying Lemma 1, inequality (2.5) is equivalent to

    Un+2(x)+Un1(x)>0. (2.6)

    For any positive x and n1, it is very easy to check inequality (2.6) is true. Similarly, we can consider the second inequality of Lemma 5.

    Un+1(x)+Un(x)Un+1(x)Un(x)<Un+2(x)Un+1(x)Un(x)+Un1(x)(Un(x)Un1(x)1)(Un+2(x)Un+1(x)1), (2.7)

    or

    U2n(x)Un+2(x)Un1(x)Un(x)Un+2(x)Un1(x)Un+1(x)Un+2(x)Un(x)Un+2(x)Un+1(x)Un+2(x)+U2n+1(x)Un1(x)+U2n+1(x)U2n(x)+Un(x)Un1(x)+Un+1(x)Un1(x)+Un(x)+Un+1(x)<0,

    applying Lemma 1, inequality (2.7) equivalent to

    Un+2(x)+Un1(x)+Un(x)Un1(x)+Un(x)+Un+1(x)<Un+1(x)Un+2(x). (2.8)

    For any positive x and n1, it is very easy to check inequality (2.8) is true.

    Lemma 6. For any positive integers n and x, we have

    1U2n(x)+1U2n+1(x)>1U2n(x)U2n1(x)1U2n+2(x)U2n+1(x),1U2n(x)+1U2n+1(x)<1U2n(x)U2n1(x)11U2n+2(x)U2n+1(x)1.

    Proof. The first inequality is equivalent to

    U2n(x)+U2n+1(x)U2n(x)U2n+1(x)>U2n+2(x)U2n+1(x)U2n(x)+U2n1(x)(U2n+2(x)U2n+1(x))(U2n(x)U2n1(x)), (2.9)

    or

    [U2n(x)+U2n+1(x)](U2n+2(x)U2n+1(x))(U2n(x)U2n1(x))>U2n(x)U2n+1(x)[U2n+2(x)U2n+1(x)U2n(x)+U2n1(x)],

    Then we have

    U4n(x)U2n+2(x)U2n(x)U2n+2(x)U2n1(x)U2n+1(x)U2n+2(x)U2n1(x)+U4n+1(x)U2n1(x)>0,

    applying Lemma 1, inequality (2.9) is equivalent to

    U2n+2(x)+2Un1(x)Un+1(x)U2n+2(x)+U2n1(x)+2Un(x)Un+2(x)U2n1(x)>0. (2.10)

    For any positive x and n1, it is very easy to check inequality (2.10) is true. Similarly, we can consider the second inequality of Lemma 6. The second inequality is equivalent to

    U2n(x)+U2n+1(x)U2n(x)U2n+1(x)<U2n+2(x)U2n+1(x)U2n(x)+U2n1(x)(U2n+2(x)U2n+1(x)1)(U2n(x)U2n1(x)1), (2.11)

    or

    U4n(x)U2n+2(x)U4n(x)U2n(x)U2n+2(x)U2n1(x)U2n+1(x)U2n+2(x)U2n1(x)+U4n+1(x)U2n1(x)+U2n(x)U2n1(x)+U2n+1(x)U2n1(x)U2n(x)U2n+2(x)U2n+1(x)U2n+2(x)+U4n+1(x)+U2n(x)+U2n+1(x)<0,

    applying Lemma 1, inequality (2.11) is equivalent to

    U2n(x)U2n1(x)+U2n(x)+U2n+1(x)+U2n+2(x)+2Un1(x)Un+1(x)U2n+2(x)+U2n1(x)
    2Un(x)Un+2(x)U2n1(x)+2Un(x)Un+2(x)<U2n+1(x)U2n+2(x)+2Un1(x)Un+1(x). (2.12)

    For any positive x and n1, it is very easy to check inequality (2.12) is true.

    Aiming to prove the results of the partial sums of Chebyshev polynomials, the lemmas below are necessary.

    Lemma 7. For any positive integer n2

    Tn(x)=12Un(x)12Un2(x)nk=1Tk(x)=12Un(x)+12Un1(x)12

    Prove. The general term formula of Chebyshev polynomials is as follows

    Tn(x)=12[(x+x21)n+(xx21)n]Un(x)=12x21[(x+x21)n+1(xx21)n+1]

    For convenient proving, we set α=x+x21, β=xx21, and easily verify α+β=2x, αβ=1. Thus, according to the definition we get

    12Un(x)12Un2(x)=12(αn+1βn+1αβαn1βn1αβ)=12(αβ)[αn1(α21)βn1(β21)]=12(αβ)[αn1(α2αβ)βn1(β2αβ)]=12(αβ)[αn(αβ)+βn(αβ)]=12(αn+βn).

    This proves the first equation. And next we prove the second equation

    nk=1Tk(x)=12nk=2Uk(x)12nk=2Uk2(x)+T1(x)=12nk=2Uk(x)12n2k=0Uk(x)+T1(x)=12Un(x)+12Un1(x)T1(x)12+T1(x)=12Un(x)+12Un1(x)12.

    This proves Lemma 7.

    Lemma 8. For any positive integer n

    2nk=1Uk(x)=Un1(x)Un(x)+Un1(x)Un+1(x), (2.13)
    2n1k=1Uk(x)=Un2(x)Un(x)+Un1(x)Un(x). (2.14)

    Prove. In accordance of the general term formula of Chebyshev polynomials, it is not hard to get

    U2n+1(x)=Un(x)Un+1(x)Un(x)Un1(x),U2n+2(x)=U2n+1(x)Un+1(x)Un1(x)1,U2n+1(x)=Un+2(x)Un(x)+1.

    Easily test that when n=1, identical Eq (2.13) is right. Supposing that n=m, Eq (2.13) is right. Then when n=m+1,

    2m+2k=1Uk(x)=Um1(x)Um+1(x)+Um1(x)Um(x)+U2m+1(x)+U2m+2(x)=Um+1(x)Um(x)+U2m+11=Um(x)Um+2(x)+Um+1(x)Um(x).

    Applying mathematical induction, it is not hard to prove identical Eq (2.14). This proves Lemma 8.

    Lemma 9. For any positive integers n,

    2nk=0kTk(x)=12(2n+1)U2n1(x)+(n+1)U2n(x)Gn(x)2nk=0kUk(x)=12Un+1(x)+12Un(x)Gn(x)

    Prove. According to Lemma 7, we have

    n+1k=0Tk(x)=Un+1(x)+Un(x)+12.

    Through derivation on the left and right sides, we get

    nk=0(k+1)Uk(x)=Un+1(x)+Un(x)2.

    Applying Lemma 7 and Lemma 8, we obtain

    2nk=1kUk(x)=12U2n+1(x)+12U2n(x)2nk=1Uk(x)=12U2n+1(x)+12U2n(x)Gn(x)2nk=1kTk(x)=x+122nk=2kUk(x)122nk=2kUk2(x)=x+122nk=2kUk(x)122n2k=0(k+2)Uk(x)=(n+12)U2n1(x)+(n+1)U2n(x)2nk=1Uk(x)=(n+12)U2n1(x)+(n+1)U2n(x)Gn(x).

    This proves Lemma 9.

    In this section, we will prove our theorems. For the infinite sums of reciprocal Chebyshev polynomials, firstly we prove Theorem 1. For any positive integer n and x, using Lemma 4, we have

    k=n1Tk(x)=k=s(1T2k1(x)+1T2k(x))<k=s(1T2k1(x)T2k2(x)1T2k+1(x)T2k(x))=1Tn(x)Tn1(x)

    In the similar way, we have

    k=n1Tk(x)=k=s(1T2k1(x)+1T2k(x))>k=s(1T2k1(x)T2k2(x)+11T2k+1(x)T2k(x)+1)=1Tn(x)Tn1(x)+1.

    And then we have

    (k=n1Tk(x))1=Tn(x)Tn1(x)

    and then let x=Tm(x), according to Lemma 3, we can get

    (k=n1Tmk(x))1=Tmn(x)Tmnm(x)

    This proved Theorem 1.

    Next, Theorem 2 will be proved. For any positive integer n and x, using Lemma 5, we have

    k=n1Uk(x)=k=s(1U2k1(x)+1U2k(x))<k=s(1U2k1(x)U2k2(x)11U2k+1(x)U2k(x)1)=1Un(x)Un1(x)1.

    In the similar way, we have

    k=n1Uk(x)=k=s(1U2k1(x)+1U2k(x))>k=s(1U2k1(x)U2k2(x)1U2k+1(x)U2k(x))=1Un(x)Un1(x).

    And then we have

    Un(x)Un1(x)1<(k=n1Uk(x))1<Un(x)Un1(x).

    that is

    (k=n1Uk(x))1=Un(x)Un1(x)1.

    This proved Theorem 2.

    Then we shall prove Theorem 3. Using Lemma 6, we can get

    k=n1U2k(x)=k=s(1U22k1(x)+1U22k(x))<k=s(1U22k1(x)U22k2(x)11U22k+1(x)U22k(x)1)=1U2n(x)U2n1(x)1.

    In the similar way, we have

    k=n1U2k(x)=k=s(1U22k1(x)+1U22k(x))>k=s(1U22k1(x)U22k2(x)1U22k+1(x)U22k(x))=1U2n(x)U2n1(x)

    and then we can get

    (k=n1U2k(x))1=U2n(x)U2n1(x)1.

    This proved Theorem 3.

    For the partial sums of Chebyshev polynomials, firstly we shall prove Theorem 4. According to Lemma 9, we have

    2n+2k=0kTk(x)=12(2n+3)U2n+1(x)+(n+2)U2n+2(x)Gn+1(x)

    Through simultaneous derivation on the left and right sides, we deduce

    2n+1k=1k2Uk1(x)=12(2n+3)U2n+1(x)+(n+2)U2n+2(x)Gn(x).

    According to Lemma 8 and Lemma 9 we get

    2n+1k=0k2Uk(x)=2n+2k=1k2Uk1(x)22n+1k=1kUk(x)2n+1k=0Uk(x)=2n+2k=1k2Uk1(x)22n+1k=1(k+1)Uk(x)+2n+1k=0Uk(x)=(n+12)U2n+1(x)+(n+1)U2n+2(x)Gn(x)+Mn(x)+1.

    Applying Lemma 7 and Lemma 8, we get

    2nk=0k2Tk(x)=x+122nk=2k2Uk(x)122nk=2k2Uk2(x)=x+122nk=2k2Uk(x)122n2k=0(k+2)2Uk(x).

    Simplify the above, we have

    2nk=0k2Tk(x)=12(2n+1)2U2n1(x)+2(n+1)2U2n+2(x)U2n+1(x)U2n(x)

    This proved Theorem 4 and Theorem 5.

    Theorem 6 shall be proved below. According to Lemma 7 and Lemma 8, we have

    2nk=0k3Tk(x)=x+122nk=2k3Uk(x)122nk=2k3Uk2(x)=x+122nk=2k3Uk(x)122n2k=0(k+2)3Uk(x)=2n2k=2(3k2+6k+4)Uk(x)+12(2n+1)3Un(x)+4(n+1)3U2n+2(x)26x4=4(n+1)3U2n+2(x)+12(2n+1)3U2n+1(x)Gn(x)(3n+32)U2n1(x)3nU2n(x)+3Mn(x)1.

    This proved Theorem 6.

    In this paper, the infinite sums of reciprocals and the partial sums derived from Chebyshev polynomials are studied. For the infinite sums of reciprocals, we apply the floor function to the reciprocals of these sums to obtain Theorem 1, Theorem 2 and Theorem 3 involving the Chebyshev polynomials. Simultaneously, we get Theorem 4, Theorem 5 and Theorem 6 about the partial sums of Chebyshev polynomials by the relation of two types of Chebyshev polynomials. Our results can enrich the related research domain with respect to orthogonal polynomials and recursive sequences. Besides, the results are hoped to be applied into other branches of mathematics or other disciplines out of mathematics.

    The authors would like to thank Xi'an Shiyou University for the support of this research.

    The authors declare there is no conflicts of interest in this paper.



    [1] R. Hering, Oscillations in Lotka-Volterra systems of chemical reactions, J. Math. Chem., 5 (1990), 197–202. https://doi.org/10.1007/BF01166429 doi: 10.1007/BF01166429
    [2] G. Laval, R. Pellat, M. Perulli, Study of the disintegration of Langmuir waves, Plasma Physics, 11 (1969), 579–588. https://dx.doi.org/10.1088/0032-1028/11/7/003 doi: 10.1088/0032-1028/11/7/003
    [3] F. Busse, Transition to Turbulence Via the Statistical Limit Cycle Route, (eds H. Haken) Chaos and Order in Nature. Springer Series in Synergetics, Berlin: Springer, 1981. https://doi.org/10.1007/978-3-642-68304-6_4
    [4] S. Solomon, P. Richmond, Stable power laws in variable economies; Lotka-Volterra implies Pareto-Zipf, Eur. Phys. J. B., 27 (2002), 257–261. https://doi.org/10.1140/epjb/e20020152 doi: 10.1140/epjb/e20020152
    [5] M. Carfora, I. Torcicollo, Cross-Diffusion-Driven instability in a predator-prey system with fear and group defense, Mathematics, 8 (2020), 1244. https://doi.org/10.3390/math8081244 doi: 10.3390/math8081244
    [6] J. Chen, X. He, F. Chen, The influence of fear effect to a discrete-time predator-prey system with predator has other food resource, Mathematics, 9 (2021), 865. https://doi.org/10.3390/math9080865 doi: 10.3390/math9080865
    [7] H. Chen, C. Zhang, Dynamic analysis of a Leslie-Gower-type predator-prey system with the fear effect and ratio-dependent Holling III functional response, Nonlinear Anal.-Model. Control, 27 (2022), 904–926. https://doi.org/10.15388/namc.2022.27.27932 doi: 10.15388/namc.2022.27.27932
    [8] W. Allee, Animal Aggregations: A Study in General Sociology, Chicago: University of Chicago Press, 1931. https://doi.org/10.5962/bhl.title.7313
    [9] D. Jonhson, A. Liebhold, P. Tobin, O. Bjørnstad, Allee effect and pulsed invasion of the gypsy moth, Nature, 444 (2006), 361–363. https://doi.org/10.1038/nature05242 doi: 10.1038/nature05242
    [10] E. Angulo, G. Roemer, L. Berec, J. Gascoigne, F. Courchamp, Double Allee effects and extinction in the island fox, Nature, 21 (2007), 1082–1091. https://doi.org/10.1111/j.1523-1739.2007.00721.x doi: 10.1111/j.1523-1739.2007.00721.x
    [11] H. Davis, C. Taylor, J. Lambrinos, D. Strong, Pollen limitation causes an Allee effect in a wind-pollinated invasive grass (Spartina alterniflora), PNAS, 101 (2004), 13804–13807. https://doi.org/10.1073/pnas.0405230101 doi: 10.1073/pnas.0405230101
    [12] C. Taylor, A. Hastings, Finding optimal control strategies for invasive species: a density-structured model for Spartina alterniflora, J. Appl. Ecol., 41 (2004), 1049–1057. https://doi.org/10.1111/j.0021-8901.2004.00979.x doi: 10.1111/j.0021-8901.2004.00979.x
    [13] C. Celik, O. Duman, Allee effect in a discrete-time predator-prey system, Chaos Soliton. Fract., 40 (2009), 1956–1962. https://doi.org/10.1016/j.chaos.2007.09.077 doi: 10.1016/j.chaos.2007.09.077
    [14] H. Merdan, O. Duman, On the stability analysis of a general discrete-time population model involving predation and Allee effects, Chaos Soliton. Fract., 40 (2009), 1169–1175. https://doi.org/10.1016/j.chaos.2007.08.081 doi: 10.1016/j.chaos.2007.08.081
    [15] O. Duman, H. Merdan, Stability analysis of continuous population model involving predation and Allee effect, Chaos Soliton. Fract., 41 (2009), 1218–1222. https://doi.org/10.1016/j.chaos.2008.05.008 doi: 10.1016/j.chaos.2008.05.008
    [16] S. Zhou, Y. Liu, G. Wang, The stability of predator-prey systems subject to the Allee effects, Theor. Popul. Biol., 67 (2005), 23–31. https://doi.org/10.1016/j.tpb.2004.06.007 doi: 10.1016/j.tpb.2004.06.007
    [17] H. Merdan, Stability analysis of a Lotka-Volterra type predator-prey system involving Allee effects, Anziam J., 52 (2011), 139–145. https://doi.org/10.21914/anziamj.v52i0.3418 doi: 10.21914/anziamj.v52i0.3418
    [18] X. Guan, Y. Liu, X. Xie, Stability analysis of a Lotka-Volterra type predator-prey system with Allee effect on the predator species, Commun. Math. Biol. Neurosci., 2018 (2018), Article ID 9. https://doi.org/10.28919/cmbn/3654 doi: 10.28919/cmbn/3654
    [19] F. Chen, X. Guan, X. Huang, H. Deng, Dynamic behaviors of a Lotka-Volterra type predator-prey system with Allee effect on the predator species and density dependent birth rate on the prey species, Open Math., 17 (2019), 1186–1202. https://doi.org/10.1515/math-2019-0082 doi: 10.1515/math-2019-0082
    [20] J. Wang, J. Shi, J. Wei, Predator-prey system with strong Allee effect in prey, J. Math. Biol., 62 (2011), 291–331. https://doi.org/10.1007/s00285-010-0332-1 doi: 10.1007/s00285-010-0332-1
    [21] E. González-Olivares, J. Mena-Lorca, A. Rojas-Palma, Dynamical complexities in the Leslie-Gower predator-prey model as consequences of the Allee effect on prey, Appl. Math. Model., 35 (2011), 366–381. https://doi.org/10.1016/j.apm.2010.07.001 doi: 10.1016/j.apm.2010.07.001
    [22] B. Dennis, Allee effects: population growth, critical density, and the chance of extinction, Nat. Resour Model., 3 (1989), 481–538. https://doi.org/10.1111/j.1939-7445.1989.tb00119.x doi: 10.1111/j.1939-7445.1989.tb00119.x
    [23] C. Zhang, W. Yang, Dynamic behaviors of a predator–prey model with weak additive Allee effect on prey, Nonlinear Anal.-Real., 55 (2020), 103137. https://doi.org/10.1016/j.nonrwa.2020.103137 doi: 10.1016/j.nonrwa.2020.103137
    [24] C. Ke, M. Yi, Y. Guo, Qualitative analysis of a spatiotemporal prey-predator model with additive Allee effect and fear effect, Complexity, 2022 (2022), Article ID 5715922. https://doi.org/10.1155/2022/5715922 doi: 10.1155/2022/5715922
    [25] L. Chen, T. Liu, F. Chen, Stability and bifurcation in a two-patch model with additive Allee effect, AIMS Math., 7 (2022), 536–551. doi: 10.3934/math.2022034 doi: 10.3934/math.2022034
    [26] X. He, Z. Zhu, J. Chen, F. Chen, Dynamical analysis of a Lotka Volterra commensalism model with additive Allee effect, Open Math., 20 (2022), 646–665. https://doi.org/10.1515/math-2022-0055 doi: 10.1515/math-2022-0055
    [27] M. Hamilton, O. Burger, J. DeLong, J. Brown, Population stability, cooperation, and the invasibility of the human species, PNAS, 106 (2009), 12255–12260. https://doi.org/10.1073/pnas.0905708106 doi: 10.1073/pnas.0905708106
    [28] J. Jacobs, Cooperation, optimal density and low density thresholds: yet another modification of the Logistic model, Oecologia, 64 (1984), 389–395. https://doi.org/10.1007/BF00379138 doi: 10.1007/BF00379138
    [29] R. Lande, S. Engen, B. Saether, Stochastic Population Dynamics in Ecology and Conservation, London: Oxford Univ. Press, 2003. https://doi.org/10.1093/acprof: oso/9780198525257.001.0001
    [30] Y. Zhang, Y. Fan, M. Liu, Analysis of a stochastic single‑species model with intraspecific cooperation, Methodol. Comput. Appl., 24 (2022), 3101–3120. https://doi.org/10.1007/s11009-022-09957-y doi: 10.1007/s11009-022-09957-y
  • Reader Comments
  • © 2024 the Author(s), licensee AIMS Press. This is an open access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0)
通讯作者: 陈斌, bchen63@163.com
  • 1. 

    沈阳化工大学材料科学与工程学院 沈阳 110142

  1. 本站搜索
  2. 百度学术搜索
  3. 万方数据库搜索
  4. CNKI搜索

Metrics

Article views(1350) PDF downloads(89) Cited by(0)

Figures and Tables

Figures(6)  /  Tables(2)

Other Articles By Authors

/

DownLoad:  Full-Size Img  PowerPoint
Return
Return

Catalog