Number of intersection points of diagonals of an n-gon in general position, plus number of vertices.

A014626

Number of intersection points of diagonals of an n-gon in general position, plus number of vertices.

Terms

    a(0) =0a(1) =1a(2) =2a(3) =3a(4) =5a(5) =10a(6) =21a(7) =42a(8) =78a(9) =135a(10) =220a(11) =341a(12) =507a(13) =728a(14) =1015a(15) =1380a(16) =1836a(17) =2397a(18) =3078a(19) =3895a(20) =4865a(21) =6006a(22) =7337a(23) =8878a(24) =10650a(25) =12675a(26) =14976a(27) =17577a(28) =20503a(29) =23780

External references