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 A109143 #14 Dec 11 2017 11:10:44 %S A109143 1,24,-486,18960,-866028,43409520,-2305522278,127386486480, %T A109143 -7243559214894,420974335099176,-24888628571711040, %U A109143 1491922400816664432,-90454843306100805420,5536766153219810009520,-341663245004722577661324,21230836457057377337055600,-1327296238831338778081286796 %N A109143 G.f.: cube root of theta series of E_6 lattice (cf. A004007). %H A109143 Vaclav Kotesovec, <a href="/A109143/b109143.txt">Table of n, a(n) for n = 0..540</a> %H A109143 N. Heninger, E. M. Rains and N. J. A. Sloane, <a href="http://arXiv.org/abs/math.NT/0509316">On the Integrality of n-th Roots of Generating Functions</a>, J. Combinatorial Theory, Series A, 113 (2006), 1732-1745. %F A109143 a(n) ~ -(-1)^n * c * d^n / n^(4/3), where d = 68.1926041339304593440433078460708736926328270041397481947611089811133711468... and c = 0.241679782171000058724170446760823529819630243406508395073992160578... - _Vaclav Kotesovec_, Dec 11 2017 %t A109143 terms = 17; QP = QPochhammer; s = (QP[q]^9/QP[q^3]^3 + 81 q QP[q^3]^9 / QP[q]^3)^(1/3) + O[q]^terms; CoefficientList[s, q] (* _Jean-François Alcover_, Jul 08 2017, after _Michael Somos_ *) %K A109143 sign %O A109143 0,2 %A A109143 _N. J. A. Sloane_ and _Nadia Heninger_, Aug 18 2005