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A131505 n, -1, n, 2n+2. 0
0, -1, 0, 2, 1, -1, 1, 4, 2, -1, 2, 6, 3, -1, 3, 8, 4, -1, 4, 10, 5, -1, 5, 12, 6, -1, 6, 14, 7, -1, 7, 16, 8, -1, 8, 18, 9, -1, 9, 20, 10, -1, 10, 22, 11, -1, 11, 24, 12, -1, 12, 26, 13, -1, 13, 28, 14, -1, 14, 30, 15, -1, 15, 32, 16, -1, 16, 34, 17, -1, 17, 36, 18, -1, 18, 38, 19, -1, 19, 40, 20, -1, 20, 42, 21, -1, 21, 44, 22, -1, 22, 46, 23 (list; graph; refs; listen; history; internal format)
OFFSET

0,4

COMMENTS

Based on A129819 (the first with 0 0).

MATHEMATICA

Flatten[Table[{n, -1, n, 2n+2}, {n, 0, 30}]] (* From Harvey P. Dale, Nov 15 2011 *)

CROSSREFS

Sequence in context: A162512 A162510 A181876 * A100092 A131508 A140130

Adjacent sequences:  A131502 A131503 A131504 * A131506 A131507 A131508

KEYWORD

sign

AUTHOR

Paul Curtz (bpcrtz(AT)free.fr), Aug 13 2007

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Last modified February 14 23:53 EST 2012. Contains 205689 sequences.