Number of unrooted triangulations of a disk with one internal node and n+3 nodes on the boundary.

A005503

Number of unrooted triangulations of a disk with one internal node and n+3 nodes on the boundary.

Terms

    a(0) =1a(1) =2a(2) =4a(3) =11a(4) =28a(5) =91a(6) =291a(7) =1004a(8) =3471a(9) =12350a(10) =44114a(11) =159519a(12) =579835a(13) =2121845a(14) =7800702a(15) =28813730a(16) =106844383a(17) =397647256a(18) =1484755972a(19) =5560561040a(20) =20881939915a(21) =78617991116a(22) =296678132514

External references