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 A384984 #6 Jun 14 2025 10:37:05 %S A384984 1,1,9,133,3185,88521,2709625,59590189,-2800437663,-743713824239, %T A384984 -109790487971479,-14561409462651435,-1895796404420991023, %U A384984 -246003292448561592359,-31576403033658804388647,-3869259020245783760710019,-407064058939470167525999935,-20441215103072839391579678175 %N A384984 E.g.f. A(x) satisfies A(x) = exp(x*A(x)/A(-x*A(x)^6)^3). %F A384984 See A384987. %o A384984 (PARI) a(n, k=-1) = if(n*k==0, 0^n, (-1)^n*k*sum(j=1, n, (-6*n+5*j+k)^(j-1)*binomial(n, j)*a(n-j, 3*j))); %Y A384984 Column k=1 of A384987. %K A384984 sign %O A384984 0,3 %A A384984 _Seiichi Manyama_, Jun 14 2025