Number of permutations of 4 copies of 1..n avoiding adjacent step pattern up, up, down, down, up, up.
A177672
Number of permutations of 4 copies of 1..n avoiding adjacent step pattern up, up, down, down, up, up.
Terms
- a(0) =1a(1) =70a(2) =34470a(3) =61633118a(4) =290404848165
External references
- oeis: A177672