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%I #6 Mar 25 2022 00:33:35

%S 1,1,2,2,2,3,2,4,3,4,3,4,6,4,5,3,6,6,8,5,6,4,6,9,8,10,6,7,4,8,9,12,10,

%T 12,7,8,5,8,12,12,15,12,14,8,9,5,10,12,16,15,18,14,16,9,10

%N A128174 * A002260.

%C Row sums = A002623: (1, 3, 7, 13, 22, 34, ...).

%F A128174 * A002260 as infinite lower triangular matrices.

%e First few rows of the triangle:

%e 1;

%e 1, 2;

%e 2, 2, 3;

%e 2, 4, 3, 4;

%e 3, 4, 6, 4, 5;

%e 3, 6, 6, 8, 5, 6;

%e 4, 6, 9, 8, 10, 6, 7;

%e ...

%Y Cf. A002260, A128174, A002623.

%K nonn,tabl

%O 1,3

%A _Gary W. Adamson_, Oct 25 2007