Number of permutations of 3 copies of 1..n avoiding adjacent step pattern up, down, up, down, up, down.
A177625
Number of permutations of 3 copies of 1..n avoiding adjacent step pattern up, down, up, down, up, down.
Terms
- a(0) =1a(1) =20a(2) =1572a(3) =320232a(4) =132684888a(5) =97774021472
External references
- oeis: A177625