Triangulations of an n-gon such that each internal vertex has valence at least 6, i.e., nonpositively curved triangulations.

A060049

Triangulations of an n-gon such that each internal vertex has valence at least 6, i.e., nonpositively curved triangulations.

Terms

    a(0) =1a(1) =0a(2) =1a(3) =1a(4) =2a(5) =5a(6) =15a(7) =50a(8) =181a(9) =697a(10) =2821a(11) =11892a(12) =51874a(13) =232974a(14) =1073070a(15) =5053029a(16) =24264565a(17) =118570292a(18) =588567257a(19) =2963358162a(20) =15114174106a(21) =78004013763a(22) =406971280545

External references