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Triangle read by rows, A000012 * A026794.
2

%I #8 Apr 02 2022 10:10:20

%S 1,2,1,4,1,1,7,2,1,1,12,3,1,1,1,19,5,2,1,1,1,30,7,3,1,1,1,1,45,11,4,2,

%T 1,1,1,1,67,15,6,3,1,1,1,1,1,97,22,8,4,2,1,1,1,1,1,139,30,11,5,3,1,1,

%U 1,1,1,1

%N Triangle read by rows, A000012 * A026794.

%C Left border = A000070: (1, 2, 4, 7, 12, 19, 30, 45, ...).

%C Second column = A000041, the partition numbers: (1, 1, 2, 3, 5, 7, 11, ...).

%C Row sums = A016905: (1, 3, 6, 11, 18, 29, 44, ...).

%F A000012 * A026794 as infinite lower triangular matrices.

%e First few rows of the triangle:

%e 1;

%e 2, 1;

%e 4, 1, 1;

%e 7, 2, 1, 1;

%e 12, 3, 1, 1, 1;

%e 19, 5, 2, 1, 1, 1;

%e 30, 7, 3, 1, 1, 1, 1;

%e ...

%Y Cf. A000041, A000070, A016905, A026794.

%K nonn,tabl

%O 1,2

%A _Gary W. Adamson_, Jan 31 2008