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A035965
Number of partitions of n into parts not of the form 17k, 17k+4 or 17k-4. Also number of partitions with at most 3 parts of size 1 and differences between parts at distance 7 are greater than 1.
0
1, 2, 3, 4, 6, 9, 12, 17, 23, 31, 41, 55, 70, 92, 118, 151, 191, 243, 303, 381, 473, 587, 723, 892, 1090, 1334, 1622, 1970, 2381, 2878, 3458, 4156, 4973, 5944, 7081, 8429, 9996, 11848, 14001, 16527, 19459, 22891, 26858, 31486, 36831, 43036, 50190
OFFSET
1,2
COMMENTS
Case k=8,i=4 of Gordon Theorem.
REFERENCES
G. E. Andrews, The Theory of Partitions, Addison-Wesley, 1976, p. 109.
FORMULA
a(n) ~ exp(2*Pi*sqrt(7*n/51)) * 7^(1/4) * sin(4*Pi/17) / (3^(1/4) * 17^(3/4) * n^(3/4)). - Vaclav Kotesovec, May 10 2018
MATHEMATICA
nmax = 60; Rest[CoefficientList[Series[Product[(1 - x^(17*k))*(1 - x^(17*k+ 4-17))*(1 - x^(17*k- 4))/(1 - x^k), {k, 1, nmax}], {x, 0, nmax}], x]] (* Vaclav Kotesovec, May 10 2018 *)
CROSSREFS
Sequence in context: A335754 A105781 A035958 * A035973 A035982 A035992
KEYWORD
nonn,easy
STATUS
approved