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%I #8 Aug 08 2015 21:32:30
%S 1,7,3,22,13,5,50,34,19,7,95,70,46,25,9,161,125,90,58,31,11,252,203,
%T 155,110,70,37,13,372,308,245,185,130,82,43,15,525,444,364,287,215,
%U 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 Triangle T(n,k) = (2k-3+4n)*(k-1-n)*(k-2-n)/6, 1<=k<=n.
%C 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 Apparently, row n contains the initial terms of row 2n-2 of A177877. - _R. J. Mathar_, Aug 31 2011
%e First few rows are:
%e 1;
%e 7, 3;
%e 22, 13, 5;
%e 50, 34, 19, 7;
%e 95, 70, 46, 25, 9;
%e ...
%p A104716 := proc(n,k) (2*k-3+4*n)*(k-1-n)*(k-2-n)/6 ; end proc:
%p seq(seq(A104716(n,k),k=1..n),n=1..15) ; # _R. J. Mathar_, Aug 31 2011
%Y Cf. A104715, A002419 (row sums).
%K nonn,tabl,easy
%O 1,2
%A _Gary W. Adamson_, Mar 20 2005
%E Closed-form definition by _R. J. Mathar_, Aug 31 2011