Number of permutations of 5 indistinguishable copies of 1..n arranged in a circle with exactly 4 adjacent element pairs in decreasing order.
A151605
Number of permutations of 5 indistinguishable copies of 1..n arranged in a circle with exactly 4 adjacent element pairs in decreasing order.
Terms
- a(0) =0a(1) =40a(2) =127260a(3) =25681280a(4) =2620321725a(5) =205881818220
External references
- oeis: A151605