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A289569
Coefficients in expansion of 1/E_14^(1/2).
5
1, 12, 98532, 22675584, 16099478436, 6580135809432, 3539736295913088, 1699883073000957696, 871767496424764386468, 438331617201642108107916, 224266585355757815798085192, 114622723650418140746841457536, 58945651172799536532104421386880
OFFSET
0,2
LINKS
FORMULA
G.f.: Product_{n>=1} (1-q^n)^(-A289029(n)/2).
a(n) ~ c * exp(2*Pi*n) / sqrt(n), where c = 0.3764946174077880880364705796802173599460310621830541667074693852949... = 2^(9/2) * Gamma(3/4)^16 / (9 * Pi^(9/2)). - Vaclav Kotesovec, Jul 09 2017, updated Mar 07 2018
MATHEMATICA
nmax = 20; CoefficientList[Series[(1 - 24*Sum[DivisorSigma[13, k]*x^k, {k, 1, nmax}])^(-1/2), {x, 0, nmax}], x] (* Vaclav Kotesovec, Jul 09 2017 *)
CROSSREFS
1/E_k^(1/2): A289565 (k=2), A289566 (k=4), A289567 (k=6), A001943 (k=8), A289568 (k=10), this sequence (k=14).
Cf. A287964 (1/E_14), A289029, A289295 (E_14^(1/2)).
Sequence in context: A076691 A272163 A289295 * A051368 A103482 A056540
KEYWORD
nonn
AUTHOR
Seiichi Manyama, Jul 08 2017
STATUS
approved