A135722 - OEIS

A135722

A000012 * A122890.

1, 1, 1, 1, 1, 2, 1, 1, 3, 5, 1, 1, 3, 15, 14, 1, 1, 3, 23, 84, 42, 1, 1, 3, 27, 244, 466, 132, 1, 1, 3, 28, 494, 2444, 2514, 429, 1, 1, 3, 28, 796, 8720, 22022, 13233, 1430, 1, 1, 3, 28, 1094, 24394, 128514, 181841, 68376, 4862

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OFFSET

0,6

COMMENTS

Row sums = A003422: (1, 2, 4, 10, 34, 154, 874, ...).

Main diagonal = A000108, the Catalan numbers: (1, 1, 2, 5, 14, 42, 132, ...).

LINKS

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

FORMULA

A000012 * A122890 as infinite lower triangular matrices.

EXAMPLE

First few rows of the triangle:

1, 1;

1, 1, 2;

1, 1, 3, 5;

1, 1, 3, 15, 14;

1, 1, 3, 23, 84, 42;

1, 1, 3, 27, 244, 466, 132;

1, 1, 3, 28, 494, 2444, 2514, 429;

...

CROSSREFS

Cf. A003422, A122890, A000108.

Sequence in context: A372760 A153899 A068098 * A258306 A049513 A121207

Adjacent sequences: A135719 A135720 A135721 * A135723 A135724 A135725

KEYWORD

nonn,tabl

AUTHOR

Gary W. Adamson, Nov 25 2007

STATUS

approved