OFFSET
1,2
LINKS
Vaclav Kotesovec, Table of n, a(n) for n = 1..10000
FORMULA
a(n) ~ exp(Pi*sqrt(n/3)) * 3^(1/4) / (2*Pi*n^(1/4)) * (1 + (18+13*Pi^2) / (48*Pi*sqrt(3*n))). - Vaclav Kotesovec, Oct 25 2016
a(n) = A036469(n) - 1. - Vaclav Kotesovec, Oct 26 2016
G.f.: -1/(1 - x) + (1/(1 - x))*Product_{k>=1} (1 + x^k). - Ilya Gutkovskiy, Dec 25 2016
EXAMPLE
G.f. = x + 2*x^2 + 4*x^3 + 6*x^4 + 9*x^5 + 13*x^6 + 18*x^7 + 24*x^8 + 32*x^9 + ...
MATHEMATICA
Table[ Sum[ PartitionsQ[k], {k, 1, n}], {n, 1, 50}]
CROSSREFS
KEYWORD
nonn
AUTHOR
STATUS
approved