OFFSET
1,18
LINKS
R. H. Hardin, Table of n, a(n) for n=1..1000
FORMULA
a(n) ~ sqrt(Pi^2 + 6*c) * exp(sqrt((2*Pi^2/3 + 4*c)*n)) / (4*sqrt(3)*Pi*n), where c = Integral_{0..infinity} log(1 - exp(-x) + exp(-9*x)) dx = -1.177746328175383925002682189470669316299189793135604988217... . - Vaclav Kotesovec, Jan 05 2016
MATHEMATICA
nmax = 100; Rest[CoefficientList[Series[Product[1 + x^(9*k)/(1-x^k), {k, 1, nmax}], {x, 0, nmax}], x]] (* Vaclav Kotesovec, Nov 28 2015 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin Jun 01 2009
STATUS
approved