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.
%I A289392 #29 Jun 16 2018 12:32:41 %S A289392 1,-6,-72,-1104,-20238,-405792,-8601840,-189317568,-4281478272, %T A289392 -98841343686,-2318973049008,-55118876238000,-1324194430710912, %U A289392 -32099173821105312,-784045854628721568,-19276683937074656064,-476644852188898489662 %N A289392 Coefficients in expansion of E_2^(1/4). %H A289392 Seiichi Manyama, <a href="/A289392/b289392.txt">Table of n, a(n) for n = 0..702</a> %F A289392 G.f.: Product_{n>=1} (1-q^n)^A289394(n). %F A289392 a(n) ~ c / (n^(5/4) * r^n), where r = A211342 = 0.03727681029645165815098078565... is the root of the equation Sum_{k>=1} A000203(k) * r^k = 1/24 and c = -0.209452682241344640265132676904094736935029272937832600102950644347... - _Vaclav Kotesovec_, Jul 08 2017 %F A289392 G.f.: Sum_{k>=0} A004984(k) * (3*f(q))^k where f(q) is Sum_{k>=1} sigma_1(k)*q^k. - _Seiichi Manyama_, Jun 16 2018 %t A289392 nmax = 20; CoefficientList[Series[(1 - 24*Sum[DivisorSigma[1, k]*x^k, {k, 1, nmax}])^(1/4), {x, 0, nmax}], x] (* _Vaclav Kotesovec_, Jul 08 2017 *) %Y A289392 E_2^(k/4): this sequence (k=1), A289291 (k=2), A289393 (k=3). %Y A289392 E_k^(1/4): this sequence (k=2), A289307 (k=4), A289326 (k=6), A289292 (k=8), A110150 (k=10), A289391 (k=14). %Y A289392 Cf. A004984, A006352 (E_2), A108091, A109817, A289394. %K A289392 sign %O A289392 0,2 %A A289392 _Seiichi Manyama_, Jul 05 2017