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%I #8 Aug 12 2015 21:16:24
%S 1,3,0,4,2,0,7,0,3,0,6,2,3,4,0,12,4,0,0,5,0,8,2,3,4,5,6,0,15,0,9,0,5,
%T 0,7,0,13,8,0,4,5,0,7,8,0,18,4,9,8,0,0,7,0,9,0,12,2,3,4,5,6,7,8,9,10,
%U 0,28,8,9,0,15,0,7,0,0,0,11
%N Triangle defined by the matrix product A126988 * A127368, read by rows.
%F T(n,k) = Sum_{j=k..n} A126988(n,j) * A127368(j,k), 1<=k<=n.
%e First few rows of the triangle are:
%e 1;
%e 3, 0;
%e 4, 2, 0;
%e 7, 0, 3, 0;
%e 6, 2, 3, 4, 0;
%e 12, 4, 0, 0, 5, 0;
%e 8, 2, 3, 4, 5, 6, 0;
%e ...
%p A127368:=proc(n, k) if igcd(n,k) = 1 then k else 0 fi end:
%p A127445 := proc(n,k)
%p add (A126988(n,j)*A127368(j,k),j=k..n) ;
%p end proc:
%p seq(seq(A127445(n,k),k=1..n),n=1..14) ; # _R. J. Mathar_, Nov 11 2011
%Y Cf. A126988, A127368, A000217 (row sums), A000203 (column k=1).
%K nonn,tabl
%O 1,2
%A _Gary W. Adamson_, Jan 14 2007
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