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 A193658 #8 Feb 19 2015 14:49:29 %S A193658 1,1,3,15,83,503,3403,25807,218451,2049687,21160667,238690847, %T A193658 2923054435,38641535143,548635554795,8328494925615,134634766604915, %U A193658 2309386642312631,41897258229334267,801610384425038911,16132033041827096451 %N A193658 Q-residue of the triangle A051162, where Q is the triangular array (t(i,j)) given by t(i,j)=1. (See Comments.) %C A193658 For the definition of Q-residue, see A193649. %F A193658 Conjecture: a(n) +(-n-4)*a(n-1) +(4*n-1)*a(n-2) +5*(-n+2)*a(n-3) +2*(n-3)*a(n-4)=0. - _R. J. Mathar_, Feb 19 2015 %t A193658 q[n_, k_] := n + k; (* A051162 *) %t A193658 r[0] = 1; r[k_] := Sum[q[k - 1, i] r[k - 1 - i], {i, 0, k - 1}] %t A193658 p[n_, k_] := n!/(k! (n - k)!); %t A193658 v[n_] := Sum[p[n, k] r[n - k], {k, 0, n}] %t A193658 Table[v[n], {n, 0, 20}] (* A193658 *) %t A193658 TableForm[Table[q[i, k], {i, 0, 4}, {k, 0, i}]] %t A193658 Table[r[k], {k, 0, 20}] (* A001340 *) %t A193658 TableForm[Table[p[n, k], {n, 0, 4}, {k, 0, n}]] %Y A193658 Cf. A051162, A193649. %K A193658 nonn %O A193658 0,3 %A A193658 _Clark Kimberling_, Aug 02 2011