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%I #9 Feb 18 2022 22:35:48
%S 1,1,3,1,0,4,1,3,0,7,1,0,0,0,6,1,3,4,0,0,12,1,0,0,0,0,0,8,1,3,0,7,0,0,
%T 0,15,1,0,4,0,0,0,0,0,13,1,3,0,0,6,0,0,0,0,18,1,0,0,0,0,0,0,0,0,0,12,
%U 1,3,4,7,0,12,0,0,0,0,0,28,1
%N Triangle T(n,k) = sigma(k) if k|n, otherwise T(n,k)=0; 1 <= k <= n.
%F T(n,k) = Sum_{j=k..n} A051731(n,j)*A130208(j,k) = A051731(n,k)*A000203(k).
%e First few rows of the triangle are:
%e 1;
%e 1, 3;
%e 1, 0, 4;
%e 1, 3, 0, 7;
%e 1, 0, 0, 0, 6;
%e 1, 3, 4, 0, 0, 12;
%e ...
%Y Cf. A000203 (sigma, diagonal n=k), A007429 (row sums), A051731.
%K nonn,tabl,easy
%O 1,3
%A _Gary W. Adamson_, Jan 19 2007
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