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 A269938 #12 Mar 29 2016 05:21:21 %S A269938 1,1,3,21,269,5501,164871,6826353,373877161,26202082729,2288805048251, %T A269938 243958190401341,31176599353144853,4706999020319020101, %U A269938 829102910675624591839,168548158717259440652601,39174415082612704149839761,10324151597447856368055425553,3062691062053211798175516784691 %N A269938 Row sums of A268434. %p A269938 A269938 := proc(n) local T; T := proc(n, k) option remember; %p A269938 if n=k then 1 elif k<0 or k>n then 0 else T(n-1,k-1)+((n-1)^2+k^2)*T(n-1,k) fi end: add(T(n, k), k=0..n) end: seq(A269938(n), n=0..18); %Y A269938 Cf. A268434. %K A269938 nonn %O A269938 0,3 %A A269938 _Peter Luschny_, Mar 08 2016