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 edges in that figure.
A337702
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 edges in that figure.
Terms
- a(0) =21a(1) =28a(2) =35a(3) =42a(4) =112a(5) =128a(6) =567a(7) =630a(8) =693a(9) =720a(10) =1417a(11) =1526a(12) =3930a(13) =4192a(14) =4454a(15) =4302a(16) =7163a(17) =7540a(18) =14700a(19) =15400a(20) =16100a(21) =16008a(22) =22900a(23) =23816a(24) =39771a(25) =41244a(26) =42717a(27) =40800a(28) =56482a(29) =58304
External references
- oeis: A337702