Number of ways to place non-intersecting diagonals in a convex (n+2)-gon so as to create no pentagons.

A253194

Number of ways to place non-intersecting diagonals in a convex (n+2)-gon so as to create no pentagons.

Terms

    a(0) =1a(1) =3a(2) =10a(3) =39a(4) =162a(5) =707a(6) =3190a(7) =14766a(8) =69719a(9) =334481a(10) =1625846a(11) =7989908a(12) =39631204a(13) =198151579a(14) =997623275a(15) =5053274850a(16) =25734158411a(17) =131680565544a(18) =676693557574

External references