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A035438
Number of partitions of n into parts 7k+4 or 7k+5.
0
0, 0, 0, 1, 1, 0, 0, 1, 1, 1, 1, 2, 1, 1, 2, 3, 2, 2, 3, 4, 3, 4, 5, 6, 5, 6, 7, 8, 8, 10, 10, 11, 12, 14, 15, 17, 18, 20, 20, 24, 26, 28, 29, 34, 36, 38, 41, 48, 50, 53, 57, 65, 67, 73, 80, 88, 91, 99, 108, 118, 123, 135, 145, 156, 165, 181, 192, 207, 221, 240, 253, 273, 292
OFFSET
1,12
FORMULA
a(n) ~ exp(2*Pi*sqrt(n/21)) * Gamma(4/7) * Gamma(5/7) / (4 * 3^(11/28) * 7^(3/28) * Pi^(5/7) * n^(25/28)). - Vaclav Kotesovec, Aug 26 2015
MATHEMATICA
nmax = 100; Rest[CoefficientList[Series[Product[1/((1 - x^(7k+4))*(1 - x^(7k+5))), {k, 0, nmax}], {x, 0, nmax}], x]] (* Vaclav Kotesovec, Aug 26 2015 *)
CROSSREFS
Sequence in context: A161091 A027347 A352131 * A029260 A205725 A091093
KEYWORD
nonn
STATUS
approved