Late-growing permutations: number of permutations of 2 indistinguishable copies of 1..n with every partial sum <= the same partial sum averaged over all permutations.

A147682

Late-growing permutations: number of permutations of 2 indistinguishable copies of 1..n with every partial sum <= the same partial sum averaged over all permutations.

Terms

    a(0) =1a(1) =1a(2) =2a(3) =30a(4) =403a(5) =18720a(6) =746192a(7) =71892912a(8) =5873837638a(9) =951265850580

External references