cp's OEIS Frontend

A104727 Triangle T(n,k) = (k-1-n)*(k-2-n)*(k^2+k+2*k*n+3*n^2+5*n)/24 read by rows, 1<=k<=n.

%I A104727 #7 Mar 30 2012 17:25:11
%S A104727 1,7,3,25,15,6,65,45,26,10,140,105,71,40,15,266,210,155,103,57,21,462,
%T A104727 378,295,215,141,77,28,750,630,511,395,285,185,100,36,1155,990,826,
%U A104727 665,510,365,235,126,45,1705,1485,1266,1050,840,640,455,291,155,55,2431,2145,1860,1578,1302,1036,785,555,353,187,66,3367,3003
%N A104727 Triangle T(n,k) = (k-1-n)*(k-2-n)*(k^2+k+2*k*n+3*n^2+5*n)/24 read by rows, 1<=k<=n.
%C A104727 The triangle is created by multiplying the lower triangular matrix A(n,k) = A000217(k) (1<=k<=n) by the lower triangular matrix B(n,k) = n-k+1 (1<=k<=n): T(n,k) = sum_{j=k..n} A(n,j)*B(j,k).
%C A104727 The commuted product B * A generates triangle A098358.
%F A104727 T(n,1) = A001296(n). - R. J. Mathar, Oct 29 2011
%e A104727 First few rows of the triangle are:
%e A104727 1;
%e A104727 7, 3;
%e A104727 25, 15, 6;
%e A104727 665, 45, 26, 10;
%e A104727 140, 105, 71, 40, 15;
%e A104727 266, 210, 155, 103, 57, 21;
%e A104727 ...
%Y A104727 Cf. A098358, A104727, A024166 (row sums).
%K A104727 nonn,easy,tabl
%O A104727 1,2
%A A104727 _Gary W. Adamson_, Mar 20 2005