OFFSET
1,2
LINKS
Andrew Howroyd, Table of n, a(n) for n = 1..100
FORMULA
a(n) ~ sqrt(2*Pi) * (9 - sqrt(3)*Pi - 3*log(2)) * 3^(n - 1) * n^(n + 5/6) / (Gamma(1/3) * exp(n)). - Vaclav Kotesovec, Jan 02 2020
MATHEMATICA
Table[Product[3*k - 2, {k, 1, n+1}] * Sum[(-1)^k/(3*k - 2), {k, 2, n+1}], {n, 1, 20}] (* Vaclav Kotesovec, Jan 02 2020 *)
PROG
(PARI) a(n)={my(s=vector(n+1, k, 3*k-2)); vecprod(s)*sum(k=2, #s, (-1)^k/s[k])} \\ Andrew Howroyd, Jan 01 2020
CROSSREFS
KEYWORD
nonn
AUTHOR
EXTENSIONS
Terms a(13) and beyond from Andrew Howroyd, Jan 01 2020
STATUS
approved