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 A104716 #8 Aug 08 2015 21:32:30 %S A104716 1,7,3,22,13,5,50,34,19,7,95,70,46,25,9,161,125,90,58,31,11,252,203, %T A104716 155,110,70,37,13,372,308,245,185,130,82,43,15,525,444,364,287,215, %U A104716 150,94,49,17,715,615,516,420,329,245,170,106,55,19,946,825,705,588,476,371,275,190,118,61,21 %N A104716 Triangle T(n,k) = (2k-3+4n)*(k-1-n)*(k-2-n)/6, 1<=k<=n. %C A104716 The triangle is created by the matrix product A158405 * A004736, regarding both as infinite lower triangular matrices, rest of the terms filled in with zeros. %C A104716 Apparently, row n contains the initial terms of row 2n-2 of A177877. - _R. J. Mathar_, Aug 31 2011 %e A104716 First few rows are: %e A104716 1; %e A104716 7, 3; %e A104716 22, 13, 5; %e A104716 50, 34, 19, 7; %e A104716 95, 70, 46, 25, 9; %e A104716 ... %p A104716 A104716 := proc(n,k) (2*k-3+4*n)*(k-1-n)*(k-2-n)/6 ; end proc: %p A104716 seq(seq(A104716(n,k),k=1..n),n=1..15) ; # _R. J. Mathar_, Aug 31 2011 %Y A104716 Cf. A104715, A002419 (row sums). %K A104716 nonn,tabl,easy %O A104716 1,2 %A A104716 _Gary W. Adamson_, Mar 20 2005 %E A104716 Closed-form definition by _R. J. Mathar_, Aug 31 2011