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%I #15 May 09 2022 18:41:56
%S 1,1,2,6,21,75,260,864,2756,8485,25365,74021,211814,596506,1658102,
%T 4560087,12431775,33648663,90537656,242420772,646489544,1718347081,
%U 4554820137,12046252361,31799943626,83818097710,220650496730,580264098939,1524688425651,4003481631675
%N Number of permutations of [n] avoiding {1324, 1342, 3412}.
%H D. Callan and 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 1 No 158.
%H <a href="/index/Rec#order_07">Index entries for linear recurrences with constant coefficients</a>, signature (11,-50,121,-167,130,-52,8).
%p (1 -10*x +41*x^2 -87*x^3 +101*x^4 -61*x^5 +15*x^6 -x^7)/((1 -x)^2*(1 -2*x)^3*(1 -3*x +x^2)) ;
%p taylor(%,x=0,40) ;
%p gfun[seriestolist](%) ;
%t LinearRecurrence[{11,-50,121,-167,130,-52,8},{1,1,2,6,21,75,260,864},30] (* _Harvey P. Dale_, May 09 2022 *)
%K nonn,easy
%O 0,3
%A _R. J. Mathar_, Nov 09 2017
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