1
vote
0answers
37 views
Non-crystallographic cluster algebras
Background
Fomin and Zelevinsky have introduced cluster algebras in an influential article. To define a cluster algebra, Fomin and Zelevinsky have defined a mutation of seeds. Her …
-1
votes
0answers
66 views
help me finding recurrent relation problem!! [closed]
Question:
A codeword is made up of the digits 0,1,2,3. A codeword is defined as legitimate if and only if it has an even number of 0’s. Let an be the number of legitimate codewords …
0
votes
0answers
44 views
Approximate closed-form solution for a recurrence
Find an (approximate) closed-form solution for $S(m, b)$.
$$S(m,b)=\sum_{i=0}^{\lfloor (e-1)/2\rfloor}{e \choose i}S(m-1, b-i) \quad +
\sum_{i=\lfloor (e-1)/2\rfloor+1}^{\ …
1
vote
1answer
79 views
Closed form solution to an iterative equation.
$f(n+1) = f(n) + f(n)^{a}$ where $a \in (0,1)$ and $n \ge 1$ with $f(1) = m$.
If $a=0$, we see $f(n) = m + n - 1$ and if $a=1$, we see $f(n) = 2^{n-1}m$. So the recursion seems t …
6
votes
3answers
260 views
References on techniques for solving equations with discontinuous functions such as floor and ceiling?
Here I describe the sort of reference I'm after with a motivating example. I am not seeking solutions to my equations on this forum; I'm quite happy to do that myself. Rather, I'm …
0
votes
1answer
95 views
Giving a general term of a recursive function, and upper bound for it
Let a constant $B \ge 1$, and let $l_1 = 0$, $b_1 = 0$ be the values of $l$ and $b$ (respectively) at time $t = 1$.
Let $l_{t+1} = l_t + 1$ if $b_i < B$, and $l_{t+1} = l_t$ ot …
1
vote
2answers
253 views
Methods for solving two variable recurrence
I have a recurrence
$$f(i,j) = 1+ \frac{N-i}{N} f(i,j-1) + \frac{i}{N} f(i-1, j)$$
$$f(i,0) = 0$$
$$f(0,j) = j$$
I would like to compute $f(N,M)$ in terms of N and M. The sys …
4
votes
3answers
255 views
Linear Recurrence Relations in 2 Variables with Variable Coefficients
Consider the following recurrence relation:
$$-2a_{n,m} +a_{n-1,m}+a_{n,m-1}=0,$$
where $a_{n,m} \in \mathbb{C}.$I would like a purely combinatorial way to understand the subspace …
2
votes
0answers
112 views
Master theorem for probabilistically inspired recurrences
Is there a general solution for multi-variable recurrences of the following form which come from Markov chain analysis?
$f(i,j,k) = p_1 f(i-1, j,k) + p_2 f(i, j-1,k) + p_3 f(i,j, …
1
vote
2answers
73 views
A recursive Double sequence related to uniform Cardinal B-spline
Given a sequence $A_n(k)$ defined as follows:
$A_0(0)=1$, $A_0(k)=0$ for all nonzero integers $k$ and
$$A_{n}(k)=(n+1-k)^2A_{n-1}(k-1)+2(n(n+1)-k^2)A_{n-1}(k)+(n+1+k)^2A_{n-1}(k+1 …
3
votes
1answer
70 views
Books request on nonlinear recurrence relations.
Hi, do you have some sort of a bibliography on advanced techniques in recurrence equations, such as nonlinear ones and others?
As I see it recurrence equations are quite similar t …
6
votes
5answers
414 views
Uniqueness of values in recurrence relations
Given an integer $k > 1$, define the sequences $X(k,n), Y(k,n)$ as follows:
$a=4k-2,$ $y_0 = 1,$ $y_1 = a + 1,y_n = ay_{n-1} - y_{n-2}$
$b = 4k + 2,$ $ x_0 = 1,$ $x_1 …
1
vote
0answers
84 views
Trying to get an idea of the maths I could use for this optimization problem
Firstly, apologies if some of the notation or terminology is odd, or if I am defining functions that have standard notation associated with them already - I am not familiar with th …
11
votes
2answers
385 views
A question on the Laurent phenomenon
This question is motivated by my answer to 109955. It gives a
recurrence relation satisfied by a function $P(n)$ whose terms a
priori are rational functions (of three variables) wi …
0
votes
0answers
168 views
Solving a linear recurrence relation with variable coefficients.
I have the following recurrence relation:
\begin{equation}
A[n]=f_A[n-1] A[n-1] + f_B[n-1]B[n-1], \\
B[n]=g_A[n-1] A[n-1] + g_B[n-1]B[n-1],
\end{equation}
where $f_{A/B}$ and $g_ …

