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A116485 Number of permutations in S_n that avoid the pattern 12453 (or equivalently, 31245). 18
1, 1, 2, 6, 24, 119, 694, 4581, 33286, 260927, 2174398, 19053058, 174094868, 1648198050, 16085475576, 161174636600, 1652590573612, 17292601075489, 184246699159418, 1995064785620557, 21919480341617102, 244015986016996763, 2749174129340156922, 31313478171012371344 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

LINKS

Yonah Biers-Ariel, Table of n, a(n) for n = 0..37

Yonah Biers-Ariel, Julia program to compute terms

Zvezdelina Stankova-Frenkel and Julian West, A new class of Wilf-equivalent permutations, arXiv:math/0103152 [math.CO], 2001.

FORMULA

Conjecture: a(n) + A158423(n) = n!. - Benedict W. J. Irwin, Mar 15 2016

The conjecture is true: All that is needed is to show that 23145 is Wilf-equivalent to 31245, but that’s obvious since they are inverses. - Doron Zeilberger and Yonah Biers-Ariel, Feb 26 2019

CROSSREFS

Representatives for the 16 Wilf-equivalence patterns of length 5 are given in A116485, A047889, and A256195-A256208. - N. J. A. Sloane, Mar 19 2015

Cf. A099952, A158423.

Sequence in context: A256203 A256204 A256205 * A256206 A052397 A047889

Adjacent sequences:  A116482 A116483 A116484 * A116486 A116487 A116488

KEYWORD

nonn

AUTHOR

Zvezdelina Stankova (stankova(AT)mills.edu), Mar 19 2006

EXTENSIONS

More terms from the Zvezdelina Stankova-Frenkel and Julian West paper. - N. J. A. Sloane, Mar 19 2015

More terms from Doron Zeilberger and Yonah Biers-Ariel, Feb 26 2019

More terms from Yonah Biers-Ariel, Mar 04 2019

STATUS

approved

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Last modified June 25 10:10 EDT 2019. Contains 324351 sequences. (Running on oeis4.)