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%I #10 May 10 2019 22:23:49
%S 1,3,1,7,4,2,13,9,6,3,21,16,12,8,4,31,25,20,15,10,5,43,36,30,24,18,12,
%T 6,57,49,42,35,28,21,14,7,73,64,56,48,40,32,24,16,8,91,81,72,63,54,45,
%U 36,27,18,9
%N Triangle read by rows, matrix product of A145677 * A004736.
%F T(n,k) = Sum_{j=k..n} A145677(n-1,j-1)*A004736(j,k), assuming column enumeration k >= 1 in A004736. - _R. J. Mathar_, Nov 05 2011
%e First few rows of the triangle:
%e 1;
%e 3, 1;
%e 7, 4, 2;
%e 13, 9, 6, 3;
%e 21, 16, 12, 8, 4;
%e 31, 25, 20, 15, 10, 5;
%e 43, 36, 30, 24, 18, 12, 6;
%e 57, 49, 42, 35, 28, 21, 14, 7;
%e 73, 64, 56, 48, 40, 32, 24, 16, 8;
%e 91, 81, 72, 63, 54, 45, 36, 27, 18, 9;
%e 111, 100, 90, 80, 70, 60, 50, 40, 30, 20, 10;
%e 133, 121, 110, 99, 88, 77, 66, 55, 44, 33, 22, 11;
%e 157, 144, 132, 120, 108, 96, 84, 72, 60, 48, 36, 24, 12;
%e ...
%p A145677 := proc(n,k)
%p if n <0 or k < 0 or k > n then
%p 0;
%p elif k = 0 then
%p 1;
%p elif k = n then
%p n ;
%p else
%p 0 ;
%p end if;
%p end proc:
%p A004736 := proc(n,k)
%p if n <0 or k < 1 or k > n then
%p 0;
%p else
%p n-k+1 ;
%p end if;
%p end proc:
%p A158841 := proc(n,k)
%p add( A145677(n-1,j-1)*A004736(j,k),j=k..n) ;
%p end proc: # _R. J. Mathar_, Nov 05 2011
%Y Cf. A145677, A002061 (column k=1), A158842 (row sums).
%K nonn,tabl,easy
%O 1,2
%A _Gary W. Adamson_ and _Roger L. Bagula_, Mar 28 2009
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