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 A159925 #14 Feb 06 2019 00:27:29
%S A159925 1,3,12,61,370,2606,20925,188772,1890773,20822481,250082522,
%T A159925 3253176309,45567394330,683783923476,10944068960451,186098265906832,
%U A159925 3350501663825617,63671208559149815,1273621946395366224
%N A159925 Row sums of triangle A159924.
%C A159925 The sum of all terms in rows 1 through m of triangle A159924 is A159926(m). A159926(m) - A159926(m-1) = A159925(m), for m >= 2.
%H A159925 Michael De Vlieger, <a href="/A159925/b159925.txt">Table of n, a(n) for n = 1..449</a>
%p A159925 A159924 := proc(n,m) option remember ; local s; if n = m then 1; else s := add(add(procname(r,c),c=1..r),r=1..n-1) ; procname(n-1,m)+s ; fi; end: A159925 := proc(n) local m; add( A159924(n,m),m=1..n) ; end: seq(A159925(n),n=1..40) ; # _R. J. Mathar_, Apr 29 2009
%t A159925 Total /@ Block[{m = 0}, NestList[Block[{w = #}, AddTo[m, Total@ w]; Append[m + w, 1]] &, {1}, 18]] (* _Michael De Vlieger_, Oct 30 2017 *)
%Y A159925 Cf. A159924, A159926.
%K A159925 nonn
%O A159925 1,2
%A A159925 _Leroy Quet_, Apr 26 2009
%E A159925 More terms from _R. J. Mathar_, Apr 29 2009