Number of permutations p of [2n] such that 0p has exactly n alternating runs.

A291677

Number of permutations p of [2n] such that 0p has exactly n alternating runs.

Terms

    a(0) =1a(1) =1a(2) =7a(3) =148a(4) =6171a(5) =425976a(6) =43979902a(7) =6346283560

External references