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A258293
Number of partitions of 3*n^2 into parts that are at most n.
5
1, 1, 7, 75, 1033, 16019, 269005, 4767088, 87914929, 1671580383, 32560379840, 646795901962, 13058489343812, 267268692575830, 5534279506641422, 115754904055926892, 2442438538492842691, 51934447672016653655, 1111872048730513043539, 23949840661000275507964
OFFSET
0,3
LINKS
FORMULA
a(n) ~ c * d^n / n^2, where d = 23.98280768122086592445663786762351573848..., c = 0.0530017980244665552354063060738409813... .
MAPLE
T:=proc(n, k) option remember; `if`(n=0 or k=1, 1, T(n, k-1) + `if`(n<k, 0, T(n-k, k))) end proc: seq(T(3*n^2, n), n=0..20);
MATHEMATICA
(* A program to compute the constant d = 23.98280768... *) With[{j=3}, r^(2*j+1)/(r-1) /.FindRoot[-PolyLog[2, 1-r] == (j+1/2)*Log[r]^2, {r, E}, WorkingPrecision->100]] (* Vaclav Kotesovec, Jun 10 2015 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Vaclav Kotesovec, May 25 2015
STATUS
approved