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Number of partitions in parts not of the form 25k, 25k+1 or 25k-1. Also number of partitions with no part of size 1 and differences between parts at distance 11 are greater than 1.
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%I #8 May 10 2018 03:31:15

%S 0,1,1,2,2,4,4,7,8,12,14,21,24,34,41,55,66,88,105,137,165,210,253,319,

%T 382,476,572,704,842,1031,1228,1492,1775,2140,2539,3047,3601,4299,

%U 5071,6023,7083,8382,9828,11584,13552,15912,18568,21736,25296,29520

%N Number of partitions in parts not of the form 25k, 25k+1 or 25k-1. Also number of partitions with no part of size 1 and differences between parts at distance 11 are greater than 1.

%C Case k=12,i=1 of Gordon Theorem.

%D G. E. Andrews, The Theory of Partitions, Addison-Wesley, 1976, p. 109.

%F a(n) ~ exp(2*Pi*sqrt(11*n/3)/5) * 11^(1/4) * sin(Pi/25) / (3^(1/4) * 5^(3/2) * n^(3/4)). - _Vaclav Kotesovec_, May 10 2018

%t nmax = 60; Rest[CoefficientList[Series[Product[(1 - x^(25*k))*(1 - x^(25*k+ 1-25))*(1 - x^(25*k- 1))/(1 - x^k), {k, 1, nmax}], {x, 0, nmax}], x]] (* _Vaclav Kotesovec_, May 10 2018 *)

%K nonn,easy

%O 1,4

%A _Olivier GĂ©rard_