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%I #7 Mar 23 2022 01:04:59
%S 1,3,1,3,3,1,3,7,5,1,3,9,10,5,1,3,13,22,18,7,1,3,15,31,34,21,7,1,3,19,
%T 51,75,65,33,9,1,3,21,64,111,120,83,36,9,1,3,25,92,196,266,238,140,52,
%U 11,1
%N A097806 * A133080 * A007318.
%C Row sums = A133600: (1, 4, 7, 16, 28, 64, 112, ...).
%F A097806 * A133080 * A007318 as infinite lower triangular matrices, where A097806 = the pairwise operator and A133080 = an interpolation operator.
%e First few rows of the triangle:
%e 1;
%e 3, 1;
%e 3, 3, 1;
%e 3, 7, 5, 1;
%e 3, 9, 10, 5, 1;
%e 3, 13, 22, 18, 7, 1;
%e ...
%p A133599aux := proc(n,k)
%p add(A097806(n,j)*A133080(j,k),j=k..n) ;
%p end proc:
%p A133599 := proc(n,k)
%p add(A133599aux(n,j)*binomial(j-1,k-1),j=k..n) ;
%p end proc: # _R. J. Mathar_, Jun 20 2015
%Y Cf. A097806, A133080, A133600.
%K nonn,tabl
%O 1,2
%A _Gary W. Adamson_, Sep 18 2007