A130313 - OEIS

A130313

A000012 * A054523.

1, 2, 1, 4, 1, 1, 6, 2, 1, 1, 10, 2, 1, 1, 1, 12, 4, 2, 1, 1, 1, 18, 4, 2, 1, 1, 1, 1, 22, 6, 2, 2, 1, 1, 1, 1, 28, 6, 4, 2, 1, 1, 1, 1, 1, 32, 10, 4, 2, 2, 1, 1, 1, 1, 1

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OFFSET

1,2

COMMENTS

Row sums = the triangular series, A000217: (1, 3, 6, 10, ...).

Left column = A002088: (1, 2, 4, 6, 10, 12, 18, ...).

LINKS

Table of n, a(n) for n=1..55.

FORMULA

A000012 * A054523 as infinite lower triangular matrices.

EXAMPLE

First few rows of the triangle:

2, 1;

4, 1, 1;

6, 2, 1, 1;

10, 2, 1, 1, 1;

12, 4, 2, 1, 1, 1;

18, 4, 2, 1, 1, 1, 1;

...

CROSSREFS

Cf. A000012, A054523, A000217.

Sequence in context: A375495 A131034 A346873 * A247073 A124428 A191310

Adjacent sequences: A130310 A130311 A130312 * A130314 A130315 A130316

KEYWORD

nonn,tabl

AUTHOR

Gary W. Adamson, May 21 2007

STATUS

approved