A289345 Coefficients in expansion of E_6^(7/12).

1, -294, -40572, -9456216, -3013531458, -1095736644072, -430427492908056, -177966281438573376, -76323096421188881292, -33643171872410204427918, -15150435131179232328586968, -6940567145625149028384495432

Offset

0,2

Links

Table of n, a(n) for n=0..11.

Formula

G.f.: Product_{n>=1} (1-q^n)^(7*A288851(n)/12).

a(n) ~ c * exp(2*Pi*n) / n^(19/12), where c = -7 * Gamma(1/12) * Gamma(1/4)^(22/3) / (1024 * 6^(1/12) * Pi^7) = -0.2836006135316422535659652380776952016594933981... - Vaclav Kotesovec, Jul 08 2017, updated Mar 05 2018

Mathematica

nmax = 20; CoefficientList[Series[(1 - 504*Sum[DivisorSigma[5, k]*x^k, {k, 1, nmax}])^(7/12), {x, 0, nmax}], x] (* Vaclav Kotesovec, Jul 08 2017 *)

Crossrefs

E_6^(k/12): A109817 (k=1), A289325 (k=2), A289326 (k=3), A289327 (k=4), A289328 (k=5), A289293 (k=6), this sequence (k=7), A289346 (k=8), A289347 (k=9), A289348 (k=10), A289349 (k=11).

Cf. A013973 (E_6), A288851.

Sequence in context: A235002 A222798 A128965 * A063049 A131274 A074868

Adjacent sequences: A289342 A289343 A289344 * A289346 A289347 A289348

Keyword

sign

Author

Seiichi Manyama, Jul 03 2017

Status

approved