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 A317798 #6 Aug 14 2018 00:32:36
%S A317798 1,15,786,69261,8554530,1359020643,263929299177,60582032629791,
%T A317798 16046282916588207,4817035600778756553,1616224504900354928832,
%U A317798 599373591433178971787007,243449152911402772344286998,107482020677618238226506065235,51249638236281451846248205583562,26247197050200652206165329786055981,14369481728948627418149559363836673273
%N A317798 G.f.: Sum_{n>=0} (3*(1+x)^n - 1)^n / 3^(n+1).
%F A317798 G.f. satisfies:
%F A317798 (1) Sum_{n>=0} 3^n * (1+x)^(n^2) / (3 + (1+x)^n)^(n+1).
%F A317798 (2) Sum_{n>=0} ((1+x)^n - 1/3)^n / 3.
%e A317798 G.f.: A(x) = 1 + 15*x + 786*x^2 + 69261*x^3 + 8554530*x^4 + 1359020643*x^5 + 263929299177*x^6 + 60582032629791*x^7 + 16046282916588207*x^8 + ...
%e A317798 such that
%e A317798 A(x) = 1/3 + (3*(1+x) - 1)/3^2 + (3*(1+x)^2 - 1)^3/3^3 + (3*(1+x)^3 - 1)^3/3^4 + (3*(1+x)^4 - 1)^4/3^5 + (3*(1+x)^5 - 1)^5/3^6 + ...
%e A317798 Also,
%e A317798 A(x) = 1/4 + 3*(1+x)/(3 + (1+x))^2 + 3^2*(1+x)^4/(3 + (1+x)^2)^3 + 3^3*(1+x)^9/(3 + (1+x)^3)^4 + 3^4*(1+x)^16/(3 + (1+x)^4)^5 + 3^5*(1+x)^25/(3 + (1+x)^5)^6 + 3^6*(1+x)^36/(3 + (1+x)^6)^7 + ...
%Y A317798 Cf. A122400, A301463, A317799, A301582.
%K A317798 nonn
%O A317798 0,2
%A A317798 _Paul D. Hanna_, Aug 14 2018