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A137948 Triangle read by rows, A000012 * A136579. 2
1, 2, 1, 3, 2, 2, 4, 3, 4, 6, 5, 4, 6, 12, 24, 6, 5, 8, 18, 48, 120, 7, 6, 10, 24, 72, 240, 720, 8, 7, 12, 30, 96, 360, 1440, 5040, 9, 8, 14, 36, 120, 480, 2160, 10080, 40320, 10, 9, 16, 42, 144, 600, 2880, 15120, 80640, 362880 (list; table; graph; refs; listen; history; internal format)
OFFSET

1,2

COMMENTS

Row sums = A014144 starting (1, 3, 7, 17, 51, 205,...).

FORMULA

As infinite lower triangular matrices, A000012 * A136579, where A000012 = (1; 1,1; 1,1,1;...) and A136579 = (1; 1,1; 1,1,2; 1,1,2,6; 1,1,2,6,24;...).

EXAMPLE

First few rows of the triangle are:

1;

2, 1;

3, 2, 2;

4, 3, 4, 6;

5, 4, 6, 12, 24;

6, 5, 8, 18, 48, 120;

7, 6, 10, 24, 72, 240, 720;

...

CROSSREFS

Cf. A136579, A014144.

Sequence in context: A132923 A144329 A141157 * A120933 A064134 A144154

Adjacent sequences:  A137945 A137946 A137947 * A137949 A137950 A137951

KEYWORD

nonn,tabl

AUTHOR

Gary W. Adamson (qntmpkt(AT)yahoo.com), Feb 28 2008

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Last modified February 15 15:20 EST 2012. Contains 205823 sequences.