A143120 A000012 * (A026741 * 0^(n-k)) * A000012, 1<=k<=n.

1, 1, 2, 3, 4, 5, 2, 5, 6, 7, 5, 7, 10, 11, 12, 3, 8, 10, 13, 14, 15, 7, 10, 15, 17, 20, 21, 22, 4, 11, 19, 21, 24, 25, 26, 9, 13, 20, 23, 28, 30, 33, 34, 35, 5, 14, 18, 25, 28, 33, 35, 38, 39, 40, 11, 16, 25, 29, 36, 39, 44, 49, 50, 51, 6, 17, 22, 31, 35, 42, 45, 50, 52, 55, 56, 57

Offset

1,3

Comments

Left border = A026741: (1, 1, 3, 2, 5, 3, 7, 4, 9,...).

Right border = A001318 starting (1, 2, 5, 7, 12, 15,...).

Row sums = A122576, unsigned: (1, 3, 12, 20, 45, 63, 112,...).

Links

Table of n, a(n) for n=1..76.

Formula

A000012 * (A026741 * 0^(n-k)) * A000012, 1<=k<=n

Example

First few rows of the triangle are:
1;
1, 2;
3, 4, 5;
2, 5, 6, 7;
5, 7, 10, 11, 12;
3, 8, 10, 13, 14, 15;
7, 10, 15, 17, 20, 21, 22;
4, 11, 14, 19, 21, 24, 25, 26;
...

Crossrefs

Cf. A026741, A001318, A122576.

Sequence in context: A309435 A043265 A194459 * A353277 A308201 A026362

Adjacent sequences: A143117 A143118 A143119 * A143121 A143122 A143123

Keyword

nonn,tabl

Author

Gary W. Adamson & Roger L. Bagula, Jul 26 2008

Status

approved