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%I #9 Sep 18 2022 19:15:53
%S 1,3,6,4,0,12,7,14,0,28,6,0,0,0,30,12,24,36,0,0,72,8,0,0,0,0,0,56,15,
%T 30,0,60,0,0,0,120,13,0,39,0,0,0,0,0,117,18,36,0,0,90,0,0,0,0,180,12,
%U 0,0,0,0,0,0,0,0,0,132,28,56,84,112,0,168,0,0,0,0,0,336
%N Triangle T(n,k) = k*sigma(n) if k divides n, else 0.
%F T(n,k) = Sum_{j=k..n} A130208(n,j)*A127093(j,k), product of the two infinite lower triangular matrices.
%F T(n,1) = A000203(n).
%F T(n,n) = A064987(n).
%e First few rows of the triangle are:
%e 1;
%e 3, 6;
%e 4, 0, 12;
%e 7, 14, 0, 28;
%e 6, 0, 0, 0, 30;
%e 12, 24, 36, 0, 0, 72;
%e ...
%Y Cf. A127093, A127573, A064987, A000203, A072861 (row sums).
%K nonn,tabl
%O 1,2
%A _Gary W. Adamson_, Jan 19 2007