A116843 - OEIS

%I #11 Nov 05 2025 15:22:05

%S 1,2,6,21,73,241,759,2305,6806,19652,55725,155688,429719,1174344,

%T 3183298,8571979,22958381,61220351,162668347,430978487,1139179386,

%U 3005433282,7916965441,20829348046,54747238203,143781463846

%N Number of permutations of length n which avoid the patterns 1342, 3241, 4312.

%H D. Callan, T. Mansour, <a href="https://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 96.

%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 (11,-51,130,-199,187,-105,32,-4).

%F G.f.: A(x) = -{(8x^7-26x^6+60x^5-87x^4+73x^3-35x^2+9x-1)x}/{(2x-1)^2(x-1)^4(x^2-3x+1)}

%K nonn,easy

%O 1,2

%A _Lara Pudwell_, Feb 26 2006