OFFSET
0,6
LINKS
Reinhard Zumkeller, Table of n, a(n) for n = 0..200
FORMULA
G.f.: Product_{k>=1} (1+x^(3*k))*(1+x^(3*k-1)). - Emeric Deutsch, Aug 30 2007
a(n) ~ exp(Pi*sqrt(2*n)/3) / (2^(23/12) * sqrt(3) * n^(3/4)). - Vaclav Kotesovec, Aug 24 2015
EXAMPLE
a(8)=3 because we have 8, 6+2 and 5+3.
MAPLE
g:=product((1+x^(3*k))*(1+x^(3*k-1)), k=1..30): gser:=series(g, x=0, 100): seq(coeff(gser, x, n), n=0..70); # Emeric Deutsch, Aug 30 2007
MATHEMATICA
nmax = 40; CoefficientList[Series[Product[((1+x^(3*k))*(1+x^(3*k-1))), {k, 1, nmax}], {x, 0, nmax}], x] (* Vaclav Kotesovec, Aug 24 2015 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Reinhard Zumkeller, Aug 22 2007
EXTENSIONS
a(0)=1 prepended by Vaclav Kotesovec, Aug 24 2015
STATUS
approved