A193285 - OEIS

A193285

Number of forbidden patterns of length n of the map f(x) = 4x(1-x) on the unit interval. A permutation pi is a forbidden pattern if there is no x in [0,1] such that the values x,f(x),f(f(x)),...,f^{n-1}(x) are in the same relative order as pi_1,pi_2,...,pi_n.

0, 0, 0, 1, 12, 89, 645, 4862, 39906, 361931, 3626663, 39912033

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OFFSET

0,5

COMMENTS

a(n) is also the number of forbidden patterns of length n of the tent map x -> 1-|1-2x| in [0,1].

LINKS

Table of n, a(n) for n=0..11.

S. Elizalde and Y. Liu, On basic forbidden patterns of functions, Discrete Appl. Math. 159 (2011), 1207-1216.

FORMULA

a(n) = n! - A193284(n).

EXAMPLE