login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A116838 Number of permutations of length n which avoid the patterns 1342, 3421, 4312. 0
1, 2, 6, 21, 72, 233, 719, 2146, 6260, 17968, 50967, 143278, 399960, 1110203, 3067479, 8442903, 23163006, 63371999, 172967309, 471115792, 1280844662, 3476636122, 9423007521, 25506378316, 68958653982, 186231636833 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,2
LINKS
D. Callan, T. Mansour, Enumeration of small Wilf classes avoiding 1324 and two other 4-letter patterns, arXiv:1705.00933 (2017), Table 2 No 53.
Index entries for linear recurrences with constant coefficients, signature (13,-72,222,-418,496,-369,165,-40,4).
FORMULA
G.f.: x*(x^9 -8x^8 +34x^7 -97x^6 +183x^5 -205x^4 +135x^3 -52x^2 +11x -1)/((x^2-3x+1)^2 (2x-1)^2 (x-1)^3).
MATHEMATICA
CoefficientList[Series[(x^9 - 8 x^8 + 34 x^7 - 97 x^6 + 183 x^5 - 205 x^4 + 135 x^3 - 52 x^2 + 11 x - 1)/((x^2 - 3 x + 1)^2 (2 x - 1)^2 (x - 1)^3), {x, 0, 30}], x] (* Wesley Ivan Hurt, Dec 28 2023 *)
CROSSREFS
Sequence in context: A294703 A116800 A116758 * A116836 A116796 A116779
KEYWORD
nonn,easy
AUTHOR
Lara Pudwell, Feb 26 2006
STATUS
approved

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

License Agreements, Terms of Use, Privacy Policy. .

Last modified March 29 05:48 EDT 2024. Contains 371265 sequences. (Running on oeis4.)