login
The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A294824 Number of permutations of [n] avoiding {1324, 2413, 2431}. 0

%I

%S 1,1,2,6,21,77,285,1053,3875,14212,52021,190301,696532,2553047,

%T 9377034,34525630,127466481,471935813,1752332838,6525032251,

%U 24363932865,91214649344,342358204917,1288067835421,4857138874476,18354766803127,69500599635905,263661684179088,1002016365217651

%N Number of permutations of [n] avoiding {1324, 2413, 2431}.

%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 1 No 212.

%p C := (1-sqrt(1-4*x))/2/x ;

%p 1 +x*(1 -4*x +4*x^2 -x^3 -x*(1 -4*x +2*x^2)*C)/((1 -3*x +x^2)*(1 -3*x +x^2 -x*(1 -2*x)*C)) ;

%p taylor(%,x=0,40) ;

%p gfun[seriestolist](%) ;

%K nonn,easy

%O 0,3

%A _R. J. Mathar_, Nov 09 2017

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified May 30 15:38 EDT 2020. Contains 334726 sequences. (Running on oeis4.)