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A131248 2*A004070 - A000012. 1
1, 1, 1, 1, 3, 1, 1, 3, 5, 1, 1, 3, 7, 7, 1, 1, 3, 7, 13, 9, 1, 1, 3, 7, 15, 21, 11, 1, 1, 3, 7, 15, 29, 31, 13, 1, 1, 3, 7, 15, 31, 51, 43, 15, 1, 1, 3, 7, 15, 31, 61, 83, 57, 17, 1 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

0,5

COMMENTS

Row sums = A104161: (1, 2, 5, 10, 19, 34, 59,...).

LINKS

Table of n, a(n) for n=0..54.

FORMULA

2*A004070 - A000012 as infinite lower triangular matrices. Reversal triangle of A131247, read by rows.

EXAMPLE

First few rows of the triangle are:

1;

1, 1;

1, 3, 1;

1, 3, 5, 1;

1, 3, 7, 7, 1;

1, 3, 7, 13, 9, 1;

1, 3, 7, 15, 21, 11, 1;

1, 3, 7, 15, 29, 31, 13, 1;

...

CROSSREFS

Cf. A004070, A000012, A104161, A131247.

Sequence in context: A246685 A218618 A271451 * A116445 A110291 A152027

Adjacent sequences:  A131245 A131246 A131247 * A131249 A131250 A131251

KEYWORD

nonn,tabl

AUTHOR

Gary W. Adamson, Jun 23 2007

STATUS

approved

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Last modified October 18 05:17 EDT 2018. Contains 316304 sequences. (Running on oeis4.)