Number of permutations of 4 copies of 1..n avoiding adjacent step pattern up, down, down, up, up.
A177650
Number of permutations of 4 copies of 1..n avoiding adjacent step pattern up, down, down, up, up.
Terms
- a(0) =1a(1) =70a(2) =33607a(3) =56904056a(4) =249804639258
External references
- oeis: A177650