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A035395
Number of partitions of n into parts 7k or 7k+6.
0
0, 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 1, 2, 2, 0, 0, 0, 1, 2, 4, 3, 0, 0, 1, 2, 5, 7, 5, 0, 1, 2, 5, 9, 12, 7, 1, 2, 5, 10, 17, 19, 12, 2, 5, 10, 19, 28, 31, 17, 5, 10, 20, 33, 48, 47, 27, 10, 20, 35, 58, 75, 72, 40, 20, 36, 63, 94, 119, 107, 62, 36, 65, 104, 152, 180, 159, 92, 66, 109
OFFSET
1,13
FORMULA
a(n) ~ exp(2*Pi*sqrt(n/21)) * 7^(5/28) * Gamma(6/7) / (4 * 3^(19/28) * Pi^(1/7) * n^(33/28)). - Vaclav Kotesovec, Aug 27 2015
MATHEMATICA
nmax = 100; Rest[CoefficientList[Series[Product[1/((1 - x^(7k+7))*(1 - x^(7k+6))), {k, 0, nmax}], {x, 0, nmax}], x]] (* Vaclav Kotesovec, Aug 27 2015 *)
CROSSREFS
Sequence in context: A204421 A131018 A300067 * A116856 A140344 A374355
KEYWORD
nonn
STATUS
approved