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 A384942 #9 Jun 13 2025 08:21:09 %S A384942 1,1,5,-5,-135,-110,3661,16440,-1375,-827075,-8388505,2298072, %T A384942 496514205,2782147265,322830120,-164675585390,-1846591014842, %U A384942 -3084367863270,84920580735040,845318162940805,4163798547024100,-18708392155753220,-503209620889452990,-3212928238924865090 %N A384942 G.f. A(x) satisfies A(x) = 1 + x/A(-x*A(x))^5. %F A384942 See A384945. %o A384942 (PARI) a(n, k=-1) = if(n*k==0, 0^n, (-1)^n*k*sum(j=1, n, binomial(-n+2*j+k-1, j-1)*a(n-j, 5*j)/j)); %Y A384942 Column k=1 of A384945. %Y A384942 Cf. A002294, A213104. %Y A384942 Cf. A000012, A384894, A384896, A384941, A384943. %K A384942 sign %O A384942 0,3 %A A384942 _Seiichi Manyama_, Jun 13 2025