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%I #5 Feb 15 2022 01:58:32
%S 1,3,2,7,5,3,13,10,7,4,21,17,13,9,5,31,26,21,16,11,6,43,37,31,25,19,
%T 13,7,57,50,43,36,29,22,15,8,73,65,57,49,41,33,25,17,9,91,82,73,64,55,
%U 46,37,28,19,10
%N A128132 * A004736.
%C Row sums = A006003, starting (1, 5, 15, 34, 65, 111, ...). Left border = A002061: (1, 3, 7, 13, 21, 31, 43, ...) A128139 = A004736 * A128132
%F A128132 * A004736 as infinite lower triangular matrices.
%e First few rows of the triangle:
%e 1;
%e 3, 2;
%e 7, 5, 3;
%e 13, 10, 7, 4;
%e 21, 17, 13, 9, 5;
%e 31, 26, 21, 16, 11, 6;
%e 43, 37, 31, 25, 19, 13, 7;
%e ...
%Y Cf. A128132, A004736, A006003, A004006, A128139.
%K nonn,tabl
%O 1,2
%A _Gary W. Adamson_, Feb 16 2007
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