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A131781 2*A046854 - A000012(signed). 0
1, 3, 1, 1, 3, 1, 3, 3, 3, 1, 1, 5, 5, 3, 1, 3, 5, 7, 7, 3, 1, 1, 7, 11, 9, 9, 3, 1, 3, 7, 13, 19, 11, 11, 3, 1, 1, 9, 19, 21, 29, 13, 13, 3, 1, 3, 9, 21, 39, 31, 41, 15, 15, 3, 1 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Row sums = A131780: (1, 4, 5, 10, 15, 26, 41,...), a sequence with a(n)/a(n-1) tending to phi. A131779 is a companion triangle, same row sums.

LINKS

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

FORMULA

2*A046854 - A000012(signed by columns + - + -,...).

EXAMPLE

First few rows of the triangle are:

1;

3, 1;

1, 3, 1;

3, 3, 3, 1;

1, 5, 5, 3, 1;

3, 5, 7, 7, 3, 1;

1, 7, 11, 9, 9, 3, 1;

3, 7, 13, 19, 11, 11, 3, 1;

...

CROSSREFS

Cf. A131779, A131780, A046854, A000012.

Sequence in context: A131775 A218825 A035691 * A082465 A226856 A131327

Adjacent sequences:  A131778 A131779 A131780 * A131782 A131783 A131784

KEYWORD

nonn,tabl

AUTHOR

Gary W. Adamson, Jul 14 2007

STATUS

approved

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Last modified June 24 22:15 EDT 2019. Contains 324337 sequences. (Running on oeis4.)