Place two n-gons with radii 1 and 2 concentrically, forming an annular area between them. Connect all the vertices with line segments that lie entirely within that area. Then a(n) is the number of vertices in that figure.
A337701
Place two n-gons with radii 1 and 2 concentrically, forming an annular area between them. Connect all the vertices with line segments that lie entirely within that area. Then a(n) is the number of vertices in that figure.
Terms
- a(0) =9a(1) =12a(2) =15a(3) =18a(4) =49a(5) =56a(6) =252a(7) =280a(8) =308a(9) =312a(10) =650a(11) =700a(12) =1845a(13) =1968a(14) =2091a(15) =1962a(16) =3401a(17) =3580a(18) =7056a(19) =7392a(20) =7728a(21) =7560a(22) =11050a(23) =11492a(24) =19305a(25) =20020a(26) =20735a(27) =19320a(28) =27497a(29) =28384
External references
- oeis: A337701