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A131047 (1/2) * ((A007318 - A007318^(-1)). 10
1, 0, 2, 1, 0, 3, 0, 4, 0, 4, 1, 0, 10, 0, 5, 0, 6, 0, 20, 0, 6, 1, 0, 21, 0, 35, 0, 7, 0, 8, 0, 56, 0, 56, 0, 8, 1, 0, 36, 0, 126, 0, 84, 0, 9 (list; table; graph; refs; listen; history; internal format)
OFFSET

1,3

COMMENTS

Row sums = (1, 2, 4, 8,...). A131047 * (1,2,3,...) = A087447 starting (1, 4, 10, 24, 56,...). A generalized set of analogous triangles: ((1/(Q+1)) * (P^Q - 1/P), Q an integer, generates triangles with row sums = powers of (Q+1). Cf. A131048, A131049, A131050, A131051 for triangles having Q = 2,3,4 and 5, respectively.

A007318, Pascal's triangle, = this triangle + A119467, since one triangle = the zeros or masks of the other. - Gary W. Adamson (qntmpkt(AT)yahoo.com), Jun 12 2007

FORMULA

Let A007318 (Pascal's triangle) = P, then A131047 = (1/2) * (P - 1/P); deleting the right border of zeros.

EXAMPLE

First few rows of the triangle are:

1;

0, 2;

1, 0, 3;

0, 4, 0, 4;

1, 0, 10, 0, 5;

0, 6, 0, 20, 0, 6;

1, 0, 21, 0, 35, 0, 7;

...

CROSSREFS

Cf. A131048, A131049, A131050, A131051.

Cf. A119467.

Sequence in context: A123973 A098493 A058560 * A143714 A004172 A082754

Adjacent sequences:  A131044 A131045 A131046 * A131048 A131049 A131050

KEYWORD

nonn,tabl

AUTHOR

Gary W. Adamson (qntmpkt(AT)yahoo.com), Jun 12 2007

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Last modified February 16 06:46 EST 2012. Contains 205867 sequences.