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A133093

A007318 * A097806 * A133080.

1, 3, 1, 6, 3, 1, 10, 6, 5, 1, 15, 10, 15, 5, 1, 21, 15, 35, 15, 7, 1, 28, 21, 70, 35, 28, 7, 1, 36, 28, 126, 70, 84, 28, 9, 1, 45, 36, 210, 126, 210, 84, 45, 9, 1, 55, 45, 330, 210, 462, 210, 165, 45, 11, 1

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OFFSET

1,2

COMMENTS

Row sums = A033484: (1, 4, 10, 22, 46, 94, ...).

LINKS

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

FORMULA

A007318 * A097806 * A133080 as infinite lower triangular matrices.

Binomial transform of an infinite lower triangular matrix with (1,1,1,...) in the main diagonal, (2,1,2,1,...) in the subdiagonal and (1,0,1,0,...) in the subsubdiagonal.

EXAMPLE

First few rows of the triangle:

3, 1;

6, 3, 1;

10, 6, 5, 1;

15, 10, 15, 5, 1;

21, 15, 35, 15, 7, 1;

28, 21, 70, 35, 28, 7, 1;

...

CROSSREFS

Cf. A133080, A097806, A033484.

Sequence in context: A249250 A122432 A131110 * A065567 A100861 A131031

Adjacent sequences: A133090 A133091 A133092 * A133094 A133095 A133096

KEYWORD

nonn,tabl

AUTHOR

Gary W. Adamson, Sep 09 2007

STATUS

approved