%I #9 Nov 08 2017 10:10:03
%S 1,2,6,21,76,278,1021,3756,13827,50916,187512,690593,2543444,9367525,
%T 34500756,127067006,467990629,1723620240,6348133335,23380322908,
%U 86110274536,317146150489,1168056674504,4301979997337,15844292751908
%N Number of permutations of length n which avoid the patterns 1234, 1243, 1432.
%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 206.
%H Lara Pudwell, <a href="http://faculty.valpo.edu/lpudwell/maple/webbook/bookmain.html">Systematic Studies in Pattern Avoidance</a>, 2005.
%H <a href="/index/Rec#order_05">Index entries for linear recurrences with constant coefficients</a>, signature (7,-17,21,-13,2).
%F G.f.: A(x) = -{x(x-1)(x^4+3x^3-5x^2+4x-1)}/{-13x^4+21x^3-17x^2+7x-1+2x^5}
%K nonn,easy
%O 1,2
%A _Lara Pudwell_, Feb 26 2006