Number of length n inversion sequences avoiding the patterns 110, 210, 120, and 010.

A279555

Number of length n inversion sequences avoiding the patterns 110, 210, 120, and 010.

Terms

    a(0) =1a(1) =1a(2) =2a(3) =5a(4) =15a(5) =51a(6) =189a(7) =746a(8) =3091a(9) =13311a(10) =59146a(11) =269701a(12) =1256820a(13) =5966001a(14) =28773252a(15) =140695923a(16) =696332678a(17) =3483193924a(18) =17589239130a(19) =89575160517a(20) =459648885327

External references