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A137593 Triangle read by rows: matrix product A000012 * A136717. 2
1, 1, 2, 1, 4, 4, 1, 4, 16, 12, 1, 4, 16, 84, 48, 1, 4, 16, 156, 504, 192, 1, 4, 16, 156, 1464, 3312, 960, 1, 4, 16, 156, 1464, 14112, 24720, 5760, 1, 4, 16, 156, 1464, 24912, 158640, 189360, 34560, 1, 4, 16, 156, 1464, 24912, 400560, 1761840, 1607040, 241920 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,3

COMMENTS

Right border = A004527: (1, 2, 4, 12, 48, 192,...). Row sums = A007489 starting (1, 3, 9, 33, 153,...).

LINKS

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

FORMULA

A000012 * A136717 as infinite lower triangular matrices.

EXAMPLE

First few rows of the triangle are:

1;

1, 2;

1, 4, 4;

1, 4, 16, 12;

1, 4, 16, 84, 48;

1, 4, 16, 156, 504, 192;

1, 4, 16, 156, 1464, 3312, 960;

...

CROSSREFS

Cf. A136717, A004527, A007489.

Sequence in context: A274980 A274826 A129862 * A009949 A070785 A214985

Adjacent sequences:  A137590 A137591 A137592 * A137594 A137595 A137596

KEYWORD

nonn,tabl

AUTHOR

Gary W. Adamson, Jan 28 2008

EXTENSIONS

Typo in eighth row corrected by Olivier Gérard, Oct 30 2012

STATUS

approved

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Last modified November 18 00:38 EST 2017. Contains 294837 sequences.