A378468 Coefficients in expansion of (1/E_4)^3.

1, -720, 339120, -132039360, 46081214640, -14974899930720, 4627836408778560, -1377759164154871680, 398508058352289409200, -112648427646194257313040, 31252327416307233967209120, -8536592939398421710286859840, 2301363255613811638678456000320, -613491781086725734777586106900960

Offset

0,2

Links

Table of n, a(n) for n=0..13.

Formula

a(n) ~ (-1)^n * 67108864 * Pi^36 * n^2 * exp(Pi*sqrt(3)*n) / (729 * Gamma(1/3)^54).

Mathematica

nmax = 20; CoefficientList[Series[(1+240*Sum[DivisorSigma[3, k]*x^k, {k, 1, nmax}])^(-3), {x, 0, nmax}], x]

Crossrefs

Cf. A004009, A001943, A287933, A378469.

Sequence in context: A222158 A374375 A145093 * A221621 A054779 A030185

Adjacent sequences: A378465 A378466 A378467 * A378469 A378470 A378471

Keyword

sign

Author

Vaclav Kotesovec, Nov 27 2024

Status

approved