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A035396
Number of partitions of n into parts 7k+1 or 7k+2.
0
1, 2, 2, 3, 3, 4, 4, 6, 7, 9, 10, 12, 13, 15, 17, 21, 24, 29, 32, 37, 40, 46, 51, 60, 67, 77, 85, 95, 104, 117, 130, 148, 164, 184, 201, 223, 243, 271, 298, 333, 365, 403, 438, 481, 525, 579, 634, 699, 761, 832, 901, 984, 1069, 1171, 1273, 1390, 1504, 1633
OFFSET
1,2
FORMULA
a(n) ~ exp(2*Pi*sqrt(n/21)) * 3^(1/28) * Gamma(1/7) * Gamma(2/7) / (4 * 7^(15/28) * Pi^(11/7) * n^(13/28)). - Vaclav Kotesovec, Aug 27 2015
MATHEMATICA
nmax = 100; Rest[CoefficientList[Series[Product[1/((1 - x^(7k+1))*(1 - x^(7k+2))), {k, 0, nmax}], {x, 0, nmax}], x]] (* Vaclav Kotesovec, Aug 27 2015 *)
CROSSREFS
Sequence in context: A108104 A173091 A029025 * A326077 A005138 A357413
KEYWORD
nonn
STATUS
approved