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A128742 Number of compositions of n with parts in N which avoid the pattern 112. 3
1, 1, 2, 4, 7, 13, 24, 43, 78, 142, 256, 463, 838, 1513, 2735, 4944, 8931, 16139, 29164, 52693, 95213, 172042, 310855, 561682, 1014898, 1833794, 3313454, 5987026, 10817836, 19546558, 35318325, 63816013, 115307993, 208347899 (list; graph; refs; listen; history; internal format)
OFFSET

0,3

LINKS

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

FORMULA

G.f.: 1/(1-sum(j>=1, X^j * prod(i=1,j-1, 1-X^(2*i)) ) )

CROSSREFS

Sequence in context: A049284 A049285 A002843 * A107281 A006744 A054175

Adjacent sequences:  A128739 A128740 A128741 * A128743 A128744 A128745

KEYWORD

nonn

AUTHOR

Ralf Stephan, May 08 2007

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Last modified February 16 09:27 EST 2012. Contains 205904 sequences.