A131398 3*A007318 - A097806 - A000012.

1, 1, 1, 2, 4, 1, 2, 8, 7, 1, 2, 11, 17, 10, 1, 2, 14, 29, 29, 13, 1, 2, 17, 44, 59, 44, 16, 1, 2, 20, 62, 104, 104, 62, 19, 1, 2, 23, 83, 167, 209, 167, 83, 22, 1, 2, 26, 107, 251, 377, 377, 251, 107, 25, 1

Offset

0,4

Comments

Row sums = A077802, (1, 2, 7, 18, 41, 88,...).

Links

Table of n, a(n) for n=0..54.

Formula

3*A007318 - A097806 - A000012 as infinite lower triangular matrices.

Example

First few rows of the triangle are:
1;
1, 1;
2, 4, 1;
2, 8, 7, 1;
2, 11, 17, 10, 1;
2, 14, 29, 29, 13, 1;
...

Crossrefs

Cf. A007318, A097806, A000012, A077802.

Sequence in context: A331696 A364837 A333651 * A249307 A209581 A342053

Adjacent sequences: A131395 A131396 A131397 * A131399 A131400 A131401

Keyword

nonn,tabl

Author

Gary W. Adamson, Jul 05 2007

Status

approved