Number of permutations p of [n] such that in 0p the largest up-jump equals 2 and no down-jump is larger than 2.

A291683

Number of permutations p of [n] such that in 0p the largest up-jump equals 2 and no down-jump is larger than 2.

Terms

    a(0) =0a(1) =0a(2) =1a(3) =3a(4) =9a(5) =25a(6) =71a(7) =205a(8) =607a(9) =1833a(10) =5635a(11) =17577a(12) =55515a(13) =177191a(14) =570699a(15) =1852571a(16) =6055079a(17) =19910729a(18) =65823751a(19) =218654099a(20) =729459551a(21) =2443051213a(22) =8210993363a(23) =27685671843a(24) =93625082139a(25) =317470233149

External references