Lucas pseudoprimes and the Pell conic

A Short Note on the Pell-Lucas-Eisenstein Series

In this work, we define a new type of Eisenstein-like series by using Pell-Lucas numbers and call them the Pell-Lucas-Eisenstein Series. Firstly, we show that the Pell-Lucas-Eisenstein series are convergent on their domain. Afterwards we prove that they satisfy some certain functional equations. Proofs follows from some on calculations on Pell-Lucas numbers.

Pell and Pell-Lucas numbers as sums of three repdigits

In this study, we find all Pell and Pell-Lucas numbers which are sums of three base 10 repdigits. The proof of our main theorem uses lower bounds for linear forms in logarithms of algebraic numbers and a version of the Baker-Davenport reduction method.

Pell and Pell-Lucas numbers as sums of two Jacobsthal numbers

We solve the two Diophantine equations $P_k=J_n+J_m$ and $Q_k=J_n+J_m$ where $\left\lbrace P_{k}\right\rbrace_{k\geq0}$, $\left\lbrace Q_{k}\right\rbrace_{k\geq0}$ and $\left\lbrace J_{k}\right\rbrace_{k\geq0}$ are the sequences of Pell numbers, Pell-Lucas numbers and Jacobsthal numbers, respectively. The main tool is the theory of linear forms in logarithms.

关于 $k$-Pell 和 $k$-Pell-Lucas 数的积分表示

On the Integral Representations of the $k$-Pell and $k$-Pell-Lucas Numbers

本文利用 Binet 公式和初等积分学，推导并验证了 $k$-Pell 和 $k$-Pell-Lucas 数的积分表示及多个恒等式，并将其结果与 Fibonacci、Lucas、Pell 和 Pell-Lucas 数相关联。

$k$-Pell-Lucas numbers as Product of Two Repdigits

For any integer $k \geq 2$, let $\{Q_{n}^{(k)} \}_{n \geq -(k-2)}$ denote the $k$-generalized Pell-Lucas sequence which starts with $0, \dots ,2,2$($k$ terms) where each next term is the sum of the $k$ preceding terms. In this paper, we find all the $k$-generalized Pell-Lucas numbers that are the product of two repdigits. This generalizes a result of Erduvan and Keskin \cite{Erduvan1} regarding repdigits of Pell-Lucas numbers.

$k$-Pell-Lucas numbers which are concatenations of two repdigits

For any integer $k \geq 2$, let $\{Q_{n}^{(k)} \}_{n \geq -(k-2)}$ denote the $k$-generalized Pell-Lucas sequence which starts with $0, \dots ,2,2$($k$ terms) where each next term is the sum of the $k$ preceding terms. In this paper, we find all the $k$-generalized Pell-Lucas numbers that are concatenations of two repdigits.

Pell数和Pell-Lucas数作为两个重复数字的差

Pell and Pell-Lucas numbers as difference of two repdigits

本文研究了Pell数和Pell-Lucas数能否表示为两个重复数字之差，并确定了所有此类数，其中最大的分别为P_6=70和Q_7=478。

关于是Pell数的Pell数与Pell-Lucas数的混合连乘问题

On Mixed Concatenations of Pell and Pell-Lucas Numbers which are Pell Numbers

该研究针对Pell序列与Pell-Lucas序列相关的两类混合连乘丢番图方程，证明其非负整数解仅有有限多组，并明确给出了进制数2到10范围内的所有解。

Solutions of the Pell equations x^2-(a^2+2a)y^2=N via generalized Fibonacci and Lucas numbers

In this study, we find continued fraction expansion of sqrt(d) when d=a^2+2a where a is positive integer. We consider the integer solutions of the Pell equation x^2-(a^2+2a)y^2=N when N={-1,+1,-4,+4}. We formulate the n-th solution (x_{n},y_{n}) by using the continued fraction expansion. We also formulate the n-th solution (x_{n},y_{n}) via the generalized Fibonacci and Lucas sequences.

On the $x$--coordinates of Pell equations which are products of two: Lucas numbers, Pell numbers

Let $ \{L_n\}_{n\ge 0} $ be the sequence of Lucas numbers given by $ L_0=2, ~ L_1=1 $ and $ L_{n+2}=L_{n+1}+L_n $ for all $ n\ge 0 $. In the first paper, for an integer $d\geq 2$ which is square-free, we show that there is at most one value of the positive integer $x$ participating in the Pell equation $x^{2}-dy^{2}=\pm 1$ which is a product of two Lucas numbers, with a few exceptions that we completely characterize. Let $ \{P_m\}_{m\ge 0} $ be the sequence of Pell numbers given by $ P_0=0, ~ P_1=1 $ and $ P_{m+2}=2P_{m+1}+P_m $ for all $ m\ge 0 $. In the second paper, for an integer $d\geq 2$…

The Generalized Fibonacci and Lucas Solutions of The Pell Equations x^2-(a^2b^2-b)y^2=N and x^2-(a^2b^2-2b)y^2=N

In this study, we find continued fraction expansion of sqrt(d) when d=a^2b^2-b and d=a^2b^2-2b where a and b are positive integers. We consider the integer solutions of the Pell equations x^2-(a^2b^2-b)y^2=N and x^2-(a^2b^2-2b)y^2=N when N is {+-1,+-4}. We formulate the n-th solution (x_{n},y_{n}) by using the continued fraction expansion. We also formulate the n-th solution (x_{n},y_{n}) in terms of generalized Fibonacci and Lucas sequences.

Construction of helices from Lucas and Fibonacci sequences

By means of two complex-valued functions (depending on an integer parameter P>=1) we construct helices of integer ratio R>=1 related to the so-called Binet formulae for P-Lucas and P-Fibonacci sequences. Based on these functions a new map is defined and we show that its three-dimensional representation is also a helix. After proving that the lattice points of these later helix satisfy certain diophantine Pell's equations we call it a Pell's helix. We prove that for P-Fibonacci and Pell's helices the respective ratio is an invariant, contrasting to the P-Lucas helices whose ratio depends on P. …

Some new identities of generalized Fibonacci and generalized Pell numbers via a new type of numbers

This paper is concerned with developing some new identities of generalized Fibonacci numbers and generalized Pell numbers. A new class of generalized numbers is introduced for this purpose. The two well-known identities of Sury and Marques which are recently developed are deduced as special cases. Moreover, some other interesting identities involving the celebrated Fibonacci, Lucas, Pell and Pell-Lucas numbers are also deduced

卢卡斯序列、皮尔方程与K3曲面的自同构

Lucas sequences, Pell's equations, and automorphisms of K3 surfaces

本文研究了卢卡斯序列、皮尔方程与 K3 曲面自同构之间的对应关系，并确定了部分序列的交集。

On Perfect Powers in k-Generalized Pell-Lucas Sequence

Let k>=2 and let (Q_{n}^{(k)})_{n>=2-k} be the k-generalized Pell sequence defined by Q_{n}^{(k)}=2Q_{n-1}^{(k)}+Q_{n-2}^{(k)}+...+Q_{n-k}^{(k)} for n>=2 with initial conditions Q_{-(k-2)}^{(k)}=Q_{-(k-3)}^{(k)}=...=Q_{-1}^{(k)}=0, Q_{0}^{(k)}=2,Q_{1}^{(k)}=2. In this paper, we solve the Diophantine equation Q_{n}^{(k)}=y^{m} in positive integers n,m,y,k with m,y,k>=2. We show that all solutions (n,m,y) of this equation in positive integers n,m,y,k such that 2<=y<=100 are given by (n,m,y)=(3,2,4),(3,4,2) for k>=3. Namely, Q_{3}^{(k)}=16=2^4=4^2 for k>=3.

Some identities for the generalized Fibonacci polynomials by the Q(x) matrix

In this note, we obtain some identities for the generalized Fibonacci polynomial by using the Q(x) matrix. These identities including the Cassini identity and Honsberger formula can be applied to some polynomial sequences, such as Fibonacci polynomials, Lucas polynomials, Pell polynomials, Pell-Lucas polynomials, Fermat polynomials, Fermat-Lucas polynomials, and so on.

Positive Integer Solutions of Certain Diophantine Equations Involving Lucas-Balancing numbers

In this article the Diophantine equations of the form $x^{2}-8C_{n}xy+ 16y^{2}=\pm2^{r}$, $x^{4}-8C_{n}x^{2}y+ 16y^{2}=\pm2^{r}$ and $x^{2}-8C_{n}xy^{2}+ 16y^{4}=\pm2^{r}$ are taken into consideration for the investigations of existence of any positive integer solutions. Furthermore, the solutions are manifested in terms of the balancing, Pell and Lucas-Pell numbers.

On the intersections of Fibonacci, Pell, and Lucas numbers

We describe how to compute the intersection of two Lucas sequences of the forms $\{U_n(P,\pm 1) \}_{n=0}^{\infty}$ or $\{V_n(P,\pm 1) \}_{n=0}^{\infty}$ with $P\in\mathbb{Z}$ that includes sequences of Fibonacci, Pell, Lucas, and Lucas-Pell numbers. We prove that such an intersection is finite except for the case $U_n(1,-1)$ and $U_n(3,1)$ and the case of two $V$-sequences when the product of their discriminants is a perfect square. Moreover, the intersection in these cases also forms a Lucas sequence. Our approach relies on solving homogeneous quadratic Diophantine equations and Thue equation…

关于Pell型序列中三项$b$-拼接产生的丢番图方程

On the Diophantine Equations Arising from Three-Term $b$-Concatenations in Pell-Type Sequences

本文研究Pell型序列中三项$b$进制拼接的丢番图方程，在中间块索引限制下给出上界，并确定$2\leq b\leq15$时的全部解数。

Ome new theorems on generating functions and their applications on odd and even certain numbers attached to p and q parameters

In this study, we first provide some new theorems by using the symmetrizing operator. After that, by using this theorems we introduce a new family of generating functions of odd and even terms of (p,q)-Fibonacci numbers, (p,q)-Lucas numbers, (p,q)-Pell numbers, (p,q)-Pell Lucas numbers, (p,q)-Jacobsthal numbers and (p,q)-Jacobsthal Lucas numbers. Then, we give the new generating functions of the products of these (p,q)-numbers with odd and even phrases of (p,q)-numbers.

Positive Integer Solutions of the Pell Equation $x^{2}-dy^{2}=N,$ $% d\in \left\{k^{2}\pm 4,\text{}k^{2}\pm 1\right\} $ and $N\in \left\{\pm 1,\pm 4\right\}

Let $\ k$ be a natural number and $d=k^{2}\pm 4$ or $k^{2}\pm 1$. In this paper, by using continued fraction expansion of $\sqrt{d},$ we find fundamental solution of the equations $x^{2}-dy^{2}=\pm 1$ and we get all positive integer solutions of the equations $x^{2}-dy^{2}=\pm 1$ in terms of generalized Fibonacci and Lucas sequences. Moreover, we find all positive integer solutions of the equations $x^{2}-dy^{2}=\pm 4$ in terms of generalized Fibonacci and Lucas sequences. Although some of the results are well known, we think our method is elementary and different from the others.

On a four-parameters generalization of some special sequences

We introduce a new four-parameters sequence that simultaneously generalizes some well-known integer sequences, including Fibonacci, Padovan, Jacobsthatl, Pell, and Lucas numbers. Combinatorial interpretations are discussed and many identities for this general sequence are derived. As a consequence, a number of identities for Fibonacci, Lucas, Pell, Jacobsthal, Padovan, and Narayana numbers as well as some of their generalizations are obtained. We also present the Cassini formula for the new sequence.

Pell和相伴Pell辫序列作为$k$个连续Pell、平衡及相关数之和的最大公约数

Pell and associated Pell braid sequences as GCDs of sums of $k$ consecutive Pell, balancing, and related numbers

研究了六个著名序列（Pell、相伴Pell、平衡及相关数）中$k$个连续项之和的最大公约数，给出了依赖$k$的闭式，并发现其可表示为Pell和相伴Pell辫序列，同时探讨了平方项之和的GCD问题。

切比雪夫、斐波那契与卢卡斯多项式之间通过三角和建立的关系

Relations between Chebyshev, Fibonacci and Lucas polynomials via trigonometric sums

本文通过有限三角和建立斐波那契、卢卡斯与切比雪夫多项式间的新恒等式，并给出其物理解释及与图有效电阻的联系。

广义斐波那契序列的多项式恒等式

Polynomial Identities for Generalized Fibonacci Sequences

该研究针对斐波那契、卢卡斯等序列的多项式恒等式，补充了广义斐波那契序列的相关恒等式，通过吉拉尔-沃林公式、比内公式结合线性代数两种方法完成序列分类，填补了数学文献中该类恒等式通用表述的空白。