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A116485 Number of permutations in S_n that avoid the pattern 12453 (or equivalently, 31245). 18

%I

%S 1,1,2,6,24,119,694,4581,33286,260927,2174398,19053058,174094868,

%T 1648198050,16085475576,161174636600,1652590573612,17292601075489,

%U 184246699159418,1995064785620557,21919480341617102,244015986016996763,2749174129340156922,31313478171012371344

%N Number of permutations in S_n that avoid the pattern 12453 (or equivalently, 31245).

%H Yonah Biers-Ariel, <a href="/A116485/b116485.txt">Table of n, a(n) for n = 0..37</a>

%H Yonah Biers-Ariel, <a href="/A116485/a116485_1.txt">Julia program to compute terms</a>

%H Zvezdelina Stankova-Frenkel and Julian West, <a href="http://arxiv.org/abs/math/0103152">A new class of Wilf-equivalent permutations</a>, arXiv:math/0103152 [math.CO], 2001.

%F Conjecture: a(n) + A158423(n) = n!. - _Benedict W. J. Irwin_, Mar 15 2016

%F 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

%Y 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

%Y Cf. A099952, A158423.

%K nonn

%O 0,3

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

%E More terms from the Zvezdelina Stankova-Frenkel and Julian West paper. - _N. J. A. Sloane_, Mar 19 2015

%E More terms from _Doron Zeilberger_ and _Yonah Biers-Ariel_, Feb 26 2019

%E More terms from _Yonah Biers-Ariel_, Mar 04 2019

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Last modified July 23 16:14 EDT 2019. Contains 325258 sequences. (Running on oeis4.)