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A177474 Avoiding the pattern 121'3. To avoid 121'3 means not to have four consecutive letters such that the first letter and the third one is less than the second and the fourth letter and the second one is less than and the fourth one. 3
1, 2, 6, 20, 83, 411, 2290, 14588, 104448 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..9.

S. Kitaev, Introduction to partially ordered patterns, Discrete Applied Mathematics 155 (2007), 929-944.

CROSSREFS

Sequence in context: A115084 A177476 A266600 * A177480 A089179 A177483

Adjacent sequences:  A177471 A177472 A177473 * A177475 A177476 A177477

KEYWORD

nonn,more

AUTHOR

Signy Olafsdottir (signy06(AT)ru.is), May 09 2010

STATUS

approved

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Last modified September 24 06:13 EDT 2021. Contains 347623 sequences. (Running on oeis4.)