OFFSET
0,9
FORMULA
a(n) ~ exp(Pi*(sqrt(2) - 1/2)*(n-4) - 4*n) * n^(4*n) / 24^n.
MATHEMATICA
Table[Product[Binomial[k-1, 4] + Binomial[n-k, 4], {k, 1, n}], {n, 0, 20}]
PROG
(PARI) a(n) = prod(k=1, n, binomial(k-1, 4) + binomial(n-k, 4)); \\ Michel Marcus, Jan 17 2019
CROSSREFS
KEYWORD
nonn
AUTHOR
Vaclav Kotesovec, Jan 16 2019
STATUS
approved