A116812 - OEIS

%I #11 Sep 17 2023 15:30:46

%S 1,2,6,21,72,229,683,1954,5452,14974,40671,109509,292743,777810,

%T 2055833,5409187,14175902,37020669,96378274,250204801,647907945,

%U 1673920904,4315683002,11105412898,28527156939,73161209063,187350573875

%N Number of permutations of length n which avoid the patterns 2314, 3421, 4123.

%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 (2017), Table 2 No 45.

%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_08">Index entries for linear recurrences with constant coefficients</a>, signature (10,-43,106,-167,174,-118,48,-9).

%F G.f.: A(x) = {x(x^9-2x^8-10x^7+35x^6-64x^5+75x^4-59x^3+29x^2-8x+1)}/{(x-1)^2(3x^3-5x^2+4x-1)^2}

%t LinearRecurrence[{10,-43,106,-167,174,-118,48,-9},{1,2,6,21,72,229,683,1954,5452,14974},40] (* _Harvey P. Dale_, Sep 17 2023 *)

%K nonn,easy

%O 1,2

%A _Lara Pudwell_, Feb 26 2006