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%I #9 Nov 08 2017 08:39:39
%S 1,2,6,21,73,240,746,2217,6371,17864,49202,133759,360175,963044,
%T 2561604,6787167,17930815,47267250,124395032,326966211,858600521,
%U 2253029402,5908876016,15490375561,40595804773,106364147270,278630854386
%N Number of permutations of length n which avoid the patterns 1234, 3142, 4132.
%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 89.
%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_06">Index entries for linear recurrences with constant coefficients</a>, signature (8,-25,39,-32,13,-2)
%F G.f.: A(x) = -{(2x^5-9x^4+16x^3-15x^2+6x-1)x}/{(2x-1)(x-1)^3(x^2-3x+1)}
%K nonn,easy
%O 1,2
%A _Lara Pudwell_, Feb 26 2006
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