A280024 - OEIS

A280024

Coefficients in q-expansion of E_2^4*E_4, where E_2 and E_4 are respectively the Eisenstein series A006352 and A004009.

1, 144, -17712, 524736, -2279088, -79760160, 71126208, 7093116288, 65399933520, 370698709968, 1592500629600, 5659924638528, 17465468914368, 48233085519456, 121766302456704, 285303917520000, 627654170451024, 1308136029869088, 2601247015228176

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OFFSET

0,2

LINKS

Seiichi Manyama, Table of n, a(n) for n = 0..1000

MATHEMATICA

terms = 19;

E2[x_] = 1 - 24*Sum[k*x^k/(1 - x^k), {k, 1, terms}];

E4[x_] = 1 + 240*Sum[k^3*x^k/(1 - x^k), {k, 1, terms}];

E2[x]^4*E4[x] + O[x]^terms // CoefficientList[#, x]& (* Jean-François Alcover, Feb 27 2018 *)

CROSSREFS

Cf. A282019 (E_2*E_4), A282208 (E_2^2*E_4), A282586 (E_2^3*E_4), this sequence (E_2^4*E_4).

Sequence in context: A352511 A260861 A079658 * A091037 A304555 A375056

Adjacent sequences: A280021 A280022 A280023 * A280025 A280026 A280027

KEYWORD

sign

AUTHOR

Seiichi Manyama, Feb 22 2017

STATUS

approved