Number of permutations of [n] in which the length of every increasing run is 0 or 1 (mod 5).

A322276

Number of permutations of [n] in which the length of every increasing run is 0 or 1 (mod 5).

Terms

    a(0) =1a(1) =1a(2) =1a(3) =1a(4) =1a(5) =2a(6) =12a(7) =72a(8) =352a(9) =1472a(10) =5756a(11) =26336a(12) =180116a(13) =1577006a(14) =13720566a(15) =109776526a(16) =829240726a(17) =6488348726a(18) =59134377126a(19) =640605185526

External references