359640

Appears in sequences

• Number of permutations of {1,...,n} avoiding adjacent step pattern up, up, down, down, down, down.at n=9A177548
• Number of 2 X 2 matrices having all terms in {1,...,n} and positive even determinant.at n=32A211067
• a(n) = n! * [x^n] (1 + x)^exp(n*x).at n=6A308333