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 A385016 #10 Jun 15 2025 09:56:53 %S A385016 1,1,5,3,-51,-190,-401,3672,51925,151539,-482538,-9063614,-79813421, %T A385016 -183787112,1737820084,22402935304,179028179329,459719628273, %U A385016 -4012720499801,-61168331089037,-556435825634630,-2299434933774430,2674772917888194,157684497102084776 %N A385016 G.f. A(x) satisfies A(x) = 1 + x*A(x)/A(-x*A(x))^4. %F A385016 See A385020. %o A385016 (PARI) a(n, k=-1) = if(n*k==0, 0^n, (-1)^n*k*sum(j=1, n, binomial(-n+j+k-1, j-1)*a(n-j, 4*j)/j)); %Y A385016 Column k=1 of A385020. %Y A385016 Cf. A384951, A385014, A385015. %Y A385016 Cf. A002294, A213233. %Y A385016 Cf. A384941. %K A385016 sign %O A385016 0,3 %A A385016 _Seiichi Manyama_, Jun 15 2025