a(n) is the number of regions formed by n-secting the angles of an octagon.

Terms

a(0) =1a(1) =8a(2) =25a(3) =104a(4) =321a(5) =80a(6) =617a(7) =624a(8) =745a(9) =1056a(10) =1617a(11) =896a(12) =2233a(13) =2224a(14) =2465a(15) =3024a(16) =3929a(17) =2472a(18) =4809a(19) =4848a(20) =5193a(21) =5944a(22) =7217a(23) =5528a(24) =8305a(25) =8456a(26) =8929a(27) =9856a(28) =11513a(29) =9336