Indices of octagonal numbers (A000567) that are also centered heptagonal numbers (A069099).
A254855
Indices of octagonal numbers (A000567) that are also centered heptagonal numbers (A069099).
Terms
- a(0) =1a(1) =2a(2) =16a(3) =43a(4) =407a(5) =1108a(6) =10558a(7) =28757a(8) =274093a(9) =746566a(10) =7115852a(11) =19381951a(12) =184738051a(13) =503184152a(14) =4796073466a(15) =13063405993a(16) =124513172057a(17) =339145371658
External references
- oeis: A254855