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This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A289393 Coefficients in expansion of E_2^(3/4).

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%I A289393 #12 Jul 08 2017 06:50:02
%S A289393 1,-18,-108,-936,-13194,-224424,-4218264,-84318336,-1759467636,
%T A289393 -37903487130,-836893437912,-18844318997496,-431163494289720,
%U A289393 -9997357777073064,-234430475682110256,-5550426839122171776,-132513976699508759994
%N A289393 Coefficients in expansion of E_2^(3/4).
%H A289393 Seiichi Manyama, <a href="/A289393/b289393.txt">Table of n, a(n) for n = 0..703</a>
%F A289393 G.f.: Product_{n>=1} (1-q^n)^(3*A289394(n)).
%F A289393 a(n) ~ c / (n^(7/4) * r^n), where r = A211342 = 0.03727681029645165815098078565... is the root of the equation Sum_{k>=1} A000203(k) * r^k = 1/24 and c = -0.22385630328806525639758543854251232523806175231599584032442913209... - _Vaclav Kotesovec_, Jul 08 2017
%t A289393 nmax = 20; CoefficientList[Series[(1 - 24*Sum[DivisorSigma[1, k]*x^k, {k, 1, nmax}])^(3/4), {x, 0, nmax}], x] (* _Vaclav Kotesovec_, Jul 08 2017 *)
%Y A289393 E_2^(k/4): A289392 (k=1), A289291 (k=2), this sequence (k=3).
%Y A289393 Cf. A006352 (E_2), A289394.
%K A289393 sign
%O A289393 0,2
%A A289393 _Seiichi Manyama_, Jul 05 2017