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 A102012 #9 Aug 08 2015 21:22:55
%S A102012 1,3,1,16,7,1,115,61,15,1,1056,626,206,31,1,11774,7554,2989,659,63,1,
%T A102012 154624,105099,47349,13308,2052,127,1,2337507,1660957,824331,274677,
%U A102012 56935,6297,255,1,39984640,29428654,15747154,5960818,1518478,237862
%N A102012 Triangle formed by right half of A101842, read by rows.
%e A102012 Triangle begins:
%e A102012 1
%e A102012 3, 1
%e A102012 16, 7, 1
%e A102012 115, 61, 15, 1
%e A102012 1056, 626, 206, 31, 1
%e A102012 11774, 7554, 2989, 659, 63, 1
%p A102012 A101842 := proc(n,k) option remember ; if k < -n or k >= n then 0 ; elif n = 1 then 1; else (n-k)*A101842(n-1,k-1)+A101842(n-1,k)+(n+k+1)*A101842(n-1,k+1) ; fi ; end: A102012 := proc(n,k) A101842(n,k-1) ; end: for n from 1 to 10 do for k from 1 to n do printf("%d, ",A102012(n,k)) ; od: od: # _R. J. Mathar_, Aug 07 2007
%K A102012 nonn,tabl
%O A102012 1,2
%A A102012 _David Applegate_, Jun 19 2007
%E A102012 More terms from _R. J. Mathar_, Aug 07 2007