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 A002302 M2093 N0828 #20 Sep 15 2024 14:12:03 %S A002302 2,16,136,1232,12096,129024,1491840,18627840,250145280,3597834240, %T A002302 55212917760,900842342400,15575854694400,284549942476800, %U A002302 5477586392678400,110832202594713600,2351805274570752000 %N A002302 Generalized tangent numbers. %D A002302 N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence). %D A002302 N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence). %D A002302 Letterio Toscano, Sulla Derivata di Ordinen della Funzione tg(x), Tohoku Math. J., 42 (1936), 144-154. %o A002302 (PARI) a(n, k)=if(k<0,0,if(n==1 && k==1,1,if(k>n,0,(k-1)*a(n-1,k-1)+(k+1)*a(n-1,k+1)))) %o A002302 for(n=0,25,print1(a(n+4, n)",")) \\ Herman Jamke (hermanjamke(AT)fastmail.fm), Nov 20 2006 %K A002302 nonn %O A002302 3,1 %A A002302 _N. J. A. Sloane_ %E A002302 More terms from Herman Jamke (hermanjamke(AT)fastmail.fm), Nov 20 2006