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 A385014 #12 Jun 15 2025 09:57:22 %S A385014 1,1,3,4,3,-15,-118,-336,-595,1467,20391,96205,353686,574786,-2717256, %T A385014 -30598208,-197828371,-841728699,-2599029153,-1309899955,56975269295, %U A385014 522707807733,3425068059553,16747743739845,63468629516172,111911654532374,-907903172853988,-12555837715110897 %N A385014 G.f. A(x) satisfies A(x) = 1 + x*A(x)/A(-x*A(x))^2. %F A385014 See A385018. %o A385014 (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, 2*j)/j)); %Y A385014 Column k=1 of A385018. %Y A385014 Cf. A384951, A385015, A385016. %Y A385014 Cf. A001764, A213228, A213229, A213230, A384974. %Y A385014 Cf. A384894. %K A385014 sign %O A385014 0,3 %A A385014 _Seiichi Manyama_, Jun 15 2025