Number of exterior points formed by extending diagonals of n-gon in general position.

Terms

a(0) =3a(1) =14a(2) =40a(3) =90a(4) =175a(5) =308a(6) =504a(7) =780a(8) =1155a(9) =1650a(10) =2288a(11) =3094a(12) =4095a(13) =5320a(14) =6800a(15) =8568a(16) =10659a(17) =13110a(18) =15960a(19) =19250a(20) =23023a(21) =27324a(22) =32200a(23) =37700a(24) =43875a(25) =50778a(26) =58464a(27) =66990a(28) =76415a(29) =86800