Number of permutations of [n] in which the length of every increasing run is 0 or 1 (mod 9).

A322298

Number of permutations of [n] in which the length of every increasing run is 0 or 1 (mod 9).

Terms

    a(0) =1a(1) =1a(2) =1a(3) =1a(4) =1a(5) =1a(6) =1a(7) =1a(8) =1a(9) =2a(10) =20a(11) =200a(12) =1520a(13) =9440a(14) =50624a(15) =242816a(16) =1066496a(17) =4361216a(18) =16856556a(19) =64202712a(20) =288983580a(21) =2160645840a(22) =24525417780a(23) =294825080160

External references