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A127651 Triangle T(n,k) = n*k if k|n, 0 otherwise; 1<=k<=n.

%I A127651 #7 Aug 18 2015 00:09:45
%S A127651 1,2,4,3,0,9,4,8,0,16,5,0,0,0,25,6,12,18,0,0,36,7,0,0,0,0,0,49,8,16,0,
%T A127651 32,0,0,0,64,9,0,27,0,0,0,0,0,81,10,20,0,0,50,0,0,0,0,100,11,0,0,0,0,
%U A127651 0,0,0,0,0,121,12,24,36,48,0,72,0,0,0,0,0,144
%N A127651 Triangle T(n,k) = n*k if k|n, 0 otherwise; 1<=k<=n.
%C A127651 Equals the matrix product A127648 * A127093 as infinite lower triangular matrices.
%F A127651 T(n,k) = n*A127093(n,k). - _R. J. Mathar_, Oct 01 2011
%e A127651 First few rows of the triangle are:
%e A127651 1;
%e A127651 2, 4;
%e A127651 3, 0, 9;
%e A127651 4, 8, 0, 16;
%e A127651 5, 0, 0, 0, 25;
%e A127651 6, 12, 18, 0, 0, 36;
%e A127651 7, 0, 0, 0, 0, 0, 49;
%e A127651 8, 16, 0, 32, 0, 0, 0, 64;
%e A127651 ...
%p A127651 A127651 := proc(n,k)
%p A127651         if n mod k =0 then
%p A127651                 n*k;
%p A127651         else
%p A127651                 0 ;
%p A127651         end if;
%p A127651 end proc: # _R. J. Mathar_, Oct 01 2011
%Y A127651 Cf. A127648, A127093, A064987 (row sums).
%K A127651 nonn,tabl,easy
%O A127651 1,2
%A A127651 _Gary W. Adamson_, Jan 22 2007