Numbers k such that k^2 is a centered 40-gonal number.

Terms

a(0) =1a(1) =11a(2) =29a(3) =199a(4) =521a(5) =3571a(6) =9349a(7) =64079a(8) =167761a(9) =1149851a(10) =3010349a(11) =20633239a(12) =54018521a(13) =370248451a(14) =969323029a(15) =6643838879a(16) =17393796001a(17) =119218851371a(18) =312119004989