Number of permutations of 4 indistinguishable copies of 1..n with exactly 4 adjacent element pairs in decreasing order.
A151642
Number of permutations of 4 indistinguishable copies of 1..n with exactly 4 adjacent element pairs in decreasing order.
Terms
- a(0) =0a(1) =1a(2) =13840a(3) =4961755a(4) =733059110a(5) =75073622025
External references
- oeis: A151642