39906

Appears in sequences

• 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.at n=8A193285
• G.f.: exp( Sum_{n>=1} (x^n/n) * Sum_{d|n} d*sigma(n/d,d) ).at n=19A198301
• G.f. A(x) satisfies A(x) = (1 + x * A(-x)) / (1 - x * A(x)).at n=10A348957
• Number of ways to partition digits 0-9 into signed terms in decreasing absolute value order with sum n.at n=24A389952