%I #9 Sep 24 2021 08:04:13
%S 1,1,2,6,21,74,249,797,2451,7318,21380,61449,174378,489827,1364499,
%T 3774779,10381722,28410568,77414615,210156558,568645563,1534219643,
%U 4128788739,11085822020,29704820778,79449163033,212145068252,565621458225,1506010540935,4004905219913
%N Number of permutations of [n] avoiding {4213, 1432, 1324}.
%H D. Callan, T. Mansour, <a href="http://arxiv.org/abs/1705.00933">Enumeration of small Wilf classes avoiding 1324 and two other 4-letter patterns</a>, arXiv:1705.00933 [math.CO] (2017), Table 2 No 122.
%H <a href="/index/Rec#order_06">Index entries for linear recurrences with constant coefficients</a>, signature (8,-25,40,-36,17,-3).
%p -(5*x^5-19*x^4+25*x^3-19*x^2+7*x-1)/((x-1)*(x^2-3*x+1)*(3*x^3-5*x^2+4*x-1)) ;
%p taylor(%,x=0,40) ;
%p gfun[seriestolist](%) ;
%K nonn,easy
%O 0,3
%A _R. J. Mathar_, Nov 08 2017
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