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Search options not deleted user 168671
0 votes
0 answers
113 views

Is the sequence $s_n:=f_{n,n} $ where $f_{0,n}=f_{n,0}= n!$ and $f_{m,n} = f_{m-1,n}+ f_{m,n...

Is the sequence $s_n:=f_{n,n} $ where $f_{0,n}=f_{n,0}= n!$ and $f_{m,n} = f_{m-1,n}+ f_{m,n-1} + f_{m-1,n-1}$ P-recursive? https://en.wikipedia.org/wiki/P-recursive_equation https://en.wikipedia.org/ …
José María Grau Ribas's user avatar
1 vote
0 answers
193 views

Why $\lim_{n\rightarrow \infty}\frac{F(n,n)}{F(n-1,n)} =\lim_{n\rightarrow \infty}\frac{F(n+...

Let $\alpha,\beta, \gamma \in \mathbb{R}^+$ be and the function $$ F(m,n)= \begin{cases} 1, & \text{if $m n=0$ }; \\ \alpha F(m ,n-1)+ \beta F(m-1,n )+ \gamma F(m-1,n-1), & \text{ if $m n>0$. }% \en …
José María Grau Ribas's user avatar
3 votes
1 answer
305 views

A generating function related to the Delannoy numbers

What is the generating function of $f_{m,n}$? $ f_{m,n} = \begin{cases} 0 , & \text{if $m<0 $ or $ n<0$ }; \\ f_{n,m} , & \text{ if $n<m$}; \\ 1, & \text{ if $0=m$ and $ n\in\{0,1\} $}; \\ …
José María Grau Ribas's user avatar
-4 votes
1 answer
301 views

Limit of recursion relation

Consider the sequence of functions $\{F_n\}_{n\in \mathbb{N}}$, where each $F_n$ is defined on $\{0,...,n\}$ by recurrence of the following form: $$ F_n(0)=3 \textrm{ and }F_n(k)=\frac{1}{k^2}+\frac{ …
José María Grau Ribas's user avatar
1 vote
1 answer
342 views

Why $\lim_{n\rightarrow \infty}\frac{F(n,n)}{F(n-1,n-1)} =\frac{9}{8}$?

$$F(m,n)= \begin{cases} 1, & \text{if $m n=0$ }; \\ \frac{1}{2} F(m ,n-1) + \frac{1}{3} F(m-1,n )+ \frac{1}{4} F(m-1,n-1), & \text{ if $m n>0$. }% \end{cases}$$ Please a proof of: $$\lim_{n\rightarro …
José María Grau Ribas's user avatar
3 votes
1 answer
144 views

About the sequence $s_n:=f_{n,n} $ where $f_{0,n}=f_{n,0}= n^n$ and $f_{m,n} = f_{m-1,n}+ f_...

Let the sequence: $s_n:=f_{n,n} $ where $f_{0,n}=f_{n,0}= n^n$ and $f_{m,n} = f_{m-1,n}+ f_{m,n-1} + f_{m-1,n-1}$, for $mn>0$. Computationally it seems that $\frac{s_{n+1}}{s_{n}} \approx e\cdot n - …
José María Grau Ribas's user avatar
0 votes
1 answer
155 views

How to probe the recursiveness order of a sequence $\{S_n\}$ whose generating function is known

How to probe the recursiveness order of a sequence $\{S_n\}$ whose generating function is known: $$ \sum_{n\geq0} S_n z^n= \frac{4 z \left(\sqrt{49 z^2-18 z+1}+7 z-1\right)}{\sqrt{49 z^2-18 z+1} …
José María Grau Ribas's user avatar
11 votes
3 answers
1k views

What is the limit of $a (n + 1) / a (n)$?

Let $a(n) = f(n,n)$ where $f(m,n) = 1$ if $m < 2 $ or $ n < 2$ and $f(m,n) = f(m-1,n-1) + f(m-1,n-2) + 2 f(m-2,n-1)$ otherwise. What is the limit of $a(n + 1) / a (n)$? $(2.71...)$
José María Grau Ribas's user avatar