Number of permutations of 4 copies of 1..n avoiding adjacent step pattern up, down, down, down, down, down.

A177657

Number of permutations of 4 copies of 1..n avoiding adjacent step pattern up, down, down, down, down, down.

Terms

    a(0) =1a(1) =1a(2) =70a(3) =34650a(4) =63063000a(5) =305540235000

External references