OFFSET
0,23
COMMENTS
Number of partitions of n into parts larger than 1 and congruent to 1 mod 5.
FORMULA
G.f.: Product_{k>=1} 1/(1 - x^(5*k+1)).
a(n) ~ Pi^(1/5) * Gamma(1/5) * exp(Pi*sqrt(2*n/15)) / (2^(21/10) * 3^(3/5) * 5^(9/10) * n^(11/10)). - Vaclav Kotesovec, Oct 09 2016
EXAMPLE
a(22) = 2, because we have [16, 6] and [11, 11].
MATHEMATICA
CoefficientList[Series[(1 - x)/QPochhammer[x, x^5], {x, 0, 100}], x]
CROSSREFS
KEYWORD
nonn
AUTHOR
Ilya Gutkovskiy, Oct 07 2016
STATUS
approved