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A127470 Triangle equal to the matrix product A127466 * A051731.

%I A127470 #6 Sep 08 2013 18:25:08
%S A127470 1,4,2,9,0,6,16,12,0,8,25,0,0,0,20,36,18,24,0,0,12,49,0,0,0,0,0,42,64,
%T A127470 56,0,48,0,0,0,32,81,0,72,0,0,0,0,0,54,100,50,0,0,80,0,0,0,0,40,121,0,
%U A127470 0,0,0,0,0,0,0,0,110,144,108,96,72,0,72,0,0,0,0,0,48
%N A127470 Triangle equal to the matrix product A127466 * A051731.
%F A127470 T(n,1) = n^2.
%F A127470 T(n,n) = n*phi(n) = A002618(n).
%e A127470 First few rows of the triangle are:
%e A127470 1;
%e A127470 4, 2;
%e A127470 9, 0, 6;
%e A127470 16, 12, 0, 8;
%e A127470 25, 0, 0, 0, 20;
%e A127470 36, 18, 24, 0, 0, 12;
%e A127470 49, 0, 0, 0, 0, 0, 42;
%e A127470 64, 56, 0, 48, 0, 0, 0, 32;
%e A127470 81, 0, 72, 0, 0, 0, 0, 0, 54;
%e A127470 ...
%p A127470 A127470 := proc(n,k)
%p A127470     add( A127466(n,j)*A051731(j,k),j=k..n) ;
%p A127470 end proc: # _R. J. Mathar_, Sep 08 2013
%Y A127470 Cf. A127466, A051731, A127469 (row sums), A061949.
%K A127470 nonn,tabl
%O A127470 1,2
%A A127470 _Gary W. Adamson_, Jan 15 2007
%E A127470 Terms corrected by _R. J. Mathar_, Sep 08 2013