A166240 Triangle read by rows, A000012 * A152140 as infinite lower triangular matrices.

1, 1, 1, 1, 1, 1, 1, 2, 1, 1, 1, 2, 2, 1, 1, 1, 3, 2, 2, 1, 1, 1, 3, 4, 2, 2, 1, 1, 1, 4, 4, 4, 2, 2, 1, 1, 1, 1, 4, 6, 4, 4, 2, 2, 1, 1, 1, 5, 6, 7, 4, 4, 2, 2, 1, 1, 1, 5, 9, 7, 7, 4, 4, 2, 2, 1, 1, 1, 6, 9, 11, 7, 7, 4, 4, 2, 2, 1, 1

Offset

1,8

Comments

Row sums = A036469, (partial sums of A000009).

The triangle = partial sums of A152140 starting from the top down, by columns.

Links

Table of n, a(n) for n=1..79.

Formula

Triangle read by rows, A000012 * A152140, where A000012 = an infinite lower triangular matrix with all 1's: [1; 1,1; 1,1,1;...].

Example

First few rows of the triangle =
1;
1, 1;
1, 1, 1;
1, 2, 1, 1;
1, 2, 2, 1, 1;
1, 3, 2, 2, 1, 1;
1, 3, 4, 2, 2, 1, 1;
1, 4, 4, 4, 2, 2, 1, 1;
1, 4, 6, 4, 4, 2, 2, 1, 1;
1, 5, 6, 7, 4, 4, 2, 2, 1, 1;
1, 5, 9, 7, 7, 4, 4, 2, 2, 1, 1;
1, 6, 9, 11, 7, 7, 4, 4, 2, 2, 1, 1;
1, 6, 12, 11, 12, 7, 7, 4, 4, 2, 2, 1, 1;
1, 7, 12, 16, 12, 12, 7, 7, 4, 4, 2, 2, 1, 1;
1, 7, 16, 16, 18, 12, 12, 7, 7, 4, 4, 2, 2, 1, 1;
1, 8, 16, 23, 18, 19, 12, 19, 7, 7, 4, 4, 2, 2, 1, 1;
...

Crossrefs

A152140, A036469, A000009

Sequence in context: A284249 A137350 A334607 * A219347 A114087 A215521

Adjacent sequences: A166237 A166238 A166239 * A166241 A166242 A166243

Keyword

nonn,tabl

Author

Gary W. Adamson, Oct 09 2009

Status

approved