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

A177668

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

Terms

    a(0) =1a(1) =70a(2) =34170a(3) =59884570a(4) =274748917668

External references