# Greetings from The On-Line Encyclopedia of Integer Sequences! http://oeis.org/ Search: id:a365990 Showing 1-1 of 1 %I A365990 #9 Sep 25 2023 07:47:14 %S A365990 1,0,0,0,6,0,0,0,2520,40320,0,0,7484400,345945600,6227020800,0, %T A365990 81729648000,7410154752000,307697854464000,6402373705728000, %U A365990 2375880867360000,354798209525760000,25460995321681920000,1090665702016450560000,26003493399464380800000 %N A365990 Expansion of e.g.f. 1 / ( 1 - Sum_{k>=0} x^(5*k+4) / (5*k+4) ). %F A365990 a(0) = 1; a(n) = Sum_{k=0..floor((n-4)/5)} (5*k+3)! * binomial(n,5*k+4) * a(n-5*k-4). %o A365990 (PARI) my(N=30, x='x+O('x^N)); Vec(serlaplace(1/(1-sum(k=0, N\5, x^(5*k+4)/(5*k+4))))) %Y A365990 Cf. A365977, A365979, A365982. %Y A365990 Cf. A365914, A365989. %K A365990 nonn %O A365990 0,5 %A A365990 _Seiichi Manyama_, Sep 25 2023 # Content is available under The OEIS End-User License Agreement: http://oeis.org/LICENSE