Number of length n inversion sequences avoiding the patterns 000, 010, 110, and 120.

A279551

Number of length n inversion sequences avoiding the patterns 000, 010, 110, and 120.

Terms

    a(0) =1a(1) =1a(2) =2a(3) =4a(4) =10a(5) =27a(6) =79a(7) =247a(8) =816a(9) =2822a(10) =10158a(11) =37875a(12) =145695a(13) =576288a(14) =2337412a(15) =9698820a(16) =41089107a(17) =177424188a(18) =779699793a(19) =3482575169a(20) =15791709187a(21) =72621800171a(22) =338388714955

External references