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%I #11 Feb 27 2021 11:05:50
%S 1,2,6,21,74,253,845,2791,9188,30246,99639,328422,1082797,3570197,
%T 11771589,38812310,127966990,421913905,1391070390,4586427029,
%U 15121681789,49856965951,164381014292,541972783322,1786912535551
%N Number of permutations of length n which avoid the patterns 1432, 2143, 3124; or avoid the patterns 1432, 2314, 3142.
%H Harvey P. Dale, <a href="/A116793/b116793.txt">Table of n, a(n) for n = 1..1000</a>
%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 (6,-12,11,-3,1).
%F G.f.: A(x) = -{(x^4-2x^3+6x^2-4x+1)x}/{x^5-3x^4+11x^3-12x^2+6x-1}
%t LinearRecurrence[{6,-12,11,-3,1},{1,2,6,21,74},30] (* _Harvey P. Dale_, Feb 27 2021 *)
%K nonn,easy
%O 1,2
%A _Lara Pudwell_, Feb 26 2006