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Triangle read by rows, n-th row = first n terms of an array formed by A051731 * A051731(transform).
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%I #6 Mar 27 2022 18:51:50

%S 1,1,2,1,1,2,1,2,1,3,1,1,1,2,1,2,2,2,1,4,1,1,1,1,1,1,2,1,2,2,2,1,4,1,

%T 1,1,1,1,1,2,1,2,1,3,1,2,1,4,1,1,2,1,1,2,1,1,3,1,2,1,2,2,2,1,2,1,4

%N Triangle read by rows, n-th row = first n terms of an array formed by A051731 * A051731(transform).

%C Row sums = sigma(n), A000203: (1, 3, 4, 7, 6, 12, 8, ...).

%C Right border = d(n), A000005: (1, 2, 2, 3, 2, 4, 2, 4, ...).

%F Given the transform A051731 * A051731(transform), extract the first n terms of each row to form the triangle.

%e First few rows of the array:

%e 1, 1, 1, 1, 1, 1, 1, ...

%e 1, 2, 1, 2, 1, 2, 1, ...

%e 1, 1, 2, 1, 1, 2, 1, ...

%e 1, 2, 1, 3, 1, 2, 1, ...

%e 1, 1, 1, 1, 2, 1, 1, ...

%e 1, 2, 2, 2, 1, 4, 1, ...

%e ...

%e First few rows of the triangle:

%e 1;

%e 1, 2;

%e 1, 1, 2;

%e 1, 2, 1, 3;

%e 1, 1, 1, 1, 2;

%e 1, 2, 2, 2, 1, 4;

%e 1, 1, 1, 1, 1, 1, 2;

%e 1, 2, 1, 3, 1, 2, 1, 4;

%e 1, 1, 2, 1, 1, 2, 1, 1, 3;

%e 1, 2, 1, 2, 2, 2, 1, 2, 1, 4;

%e ...

%Y Cf. A051731, A000203, A000005.

%K nonn,tabl

%O 1,3

%A _Gary W. Adamson_, Nov 12 2007