Number of permutations of 3 copies of 1..n avoiding adjacent step pattern up, down, up.
A177598
Number of permutations of 3 copies of 1..n avoiding adjacent step pattern up, down, up.
Terms
- a(0) =1a(1) =15a(2) =767a(3) =93621a(4) =22431655a(5) =9362799454
External references
- oeis: A177598