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 A380471 #22 Jun 23 2025 10:12:54 %S A380471 1,5,175,8625,495000,30980625,2050781250,141187921875,10006590468750, %T A380471 725240531640625,53503504196484375,4004478454589843750, %U A380471 303320955472031250000,23207794539155419921875,1791025435519151367187500,139250846557940616210937500,10897102765738964080810546875 %N A380471 G.f. A(x) satisfies A(x) = 1/( 1 - 25*x*A(x)^4 )^(1/5). %F A380471 G.f. A(x) satisfies A(x) = ( 1 + 25*x*A(x)^9 )^(1/5). %F A380471 a(n) = 25^n * binomial(9*n/5+1/5,n)/(9*n+1). %F A380471 G.f. A(x) satisfies A(x) = 1/A(-x*A(x)^13). %F A380471 G.f.: ( (1/x) * Series_Reversion(x/(1+25*x)^(9/5)) )^(1/9). %o A380471 (PARI) a(n) = 25^n*binomial(9*n/5+1/5, n)/(9*n+1); %Y A380471 Cf. A034688, A078534, A385203, A385204, A385205, A380465, A380466. %K A380471 nonn %O A380471 0,2 %A A380471 _Seiichi Manyama_, Jun 23 2025