Number of permutations of 4 indistinguishable copies of 1..n with exactly 6 adjacent element pairs in decreasing order.
A151644
Number of permutations of 4 indistinguishable copies of 1..n with exactly 6 adjacent element pairs in decreasing order.
Terms
- a(0) =0a(1) =0a(2) =1828a(3) =21571984a(4) =29066972368
External references
- oeis: A151644