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A128768 Number of peak-avoiding compositions with parts in N. 0
1, 1, 2, 4, 7, 13, 22, 38, 64, 107, 177, 293, 481, 789, 1291, 2110, 3445, 5621, 9167, 14947, 24366, 39716, 64732, 105500, 171941, 280220, 456687, 744280, 1212984, 1976850, 3221762, 5250655, 8557248, 13946172, 22728787, 37042274, 60369723 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

LINKS

Table of n, a(n) for n=0..36.

S. Heubach and T. Mansour, Enumeration of 3-letter patterns in combinations

FORMULA

The Heubach/Mansour paper has a complicated g.f.

CROSSREFS

Sequence in context: A085489 A101268 A188920 * A235607 A001036 A054150

Adjacent sequences:  A128765 A128766 A128767 * A128769 A128770 A128771

KEYWORD

nonn

AUTHOR

Ralf Stephan, May 08 2007

EXTENSIONS

More terms from Vladeta Jovovic, Oct 04 2007

STATUS

approved

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Last modified December 17 14:59 EST 2014. Contains 252022 sequences.