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 A111542 #3 Mar 30 2012 18:36:50
%S A111542 0,2,5,22,128,896,7220,65336,653720,7155104,84998768,1089232160,
%T A111542 14981704736,220233312896,3447195190592,57261708795776,
%U A111542 1006401042534272,18663532970127872,364283224523605760,7466218532765196800
%N A111542 Column 1 of triangle A111541, which is the matrix logarithm of A111536.
%C A111542 Column 0 of triangle A111541 is A111536.
%o A111542 (PARI) {a(n)=local(M=matrix(n+2,n+2,m,j,if(m==j,1,if(m==j+1,-m+1, -(m-j-1)*polcoeff(log(sum(i=0,m,(i+1)!/1!*x^i)),m-j-1))))); if(n<0,0,sum(i=1,#M,(M^0-M)^i/i)[n+2,2])}
%Y A111542 Cf. A111541 (triangle), A111538 (column 0), A111543 (column 2), A111536.
%K A111542 nonn
%O A111542 0,2
%A A111542 _Paul D. Hanna_, Aug 06 2005