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A035944
Number of partitions in parts not of the form 11k, 11k+1 or 11k-1. Also number of partitions with no part of size 1 and differences between parts at distance 4 are greater than 1.
0
0, 1, 1, 2, 2, 4, 4, 7, 8, 11, 13, 19, 22, 30, 36, 47, 56, 73, 86, 110, 131, 163, 194, 241, 284, 348, 412, 499, 588, 709, 832, 996, 1168, 1387, 1622, 1919, 2235, 2631, 3060, 3584, 4156, 4852, 5610, 6525, 7530, 8724, 10044, 11607, 13328, 15355, 17600
OFFSET
1,4
COMMENTS
Case k=5,i=1 of Gordon Theorem.
REFERENCES
G. E. Andrews, The Theory of Partitions, Addison-Wesley, 1976, p. 109.
FORMULA
a(n) ~ sqrt(2) * sin(Pi/11) * exp(4*Pi*sqrt(n/33)) / (3^(1/4) * 11^(3/4) * n^(3/4)). - Vaclav Kotesovec, Nov 21 2015
MATHEMATICA
nmax = 60; Rest[CoefficientList[Series[Product[1 / ((1 - x^(11*k-2)) * (1 - x^(11*k-3)) * (1 - x^(11*k-4)) * (1 - x^(11*k-5)) * (1 - x^(11*k-6)) * (1 - x^(11*k-7)) * (1 - x^(11*k-8)) * (1 - x^(11*k-9)) ), {k, 1, nmax}], {x, 0, nmax}], x]] (* Vaclav Kotesovec, Nov 21 2015 *)
CROSSREFS
Sequence in context: A248518 A095700 A339404 * A227134 A240013 A050366
KEYWORD
nonn,easy
STATUS
approved