A057106 Numbers k such that k(3k-2) is an octagonal palindrome.

0, 1, 2, 52, 6331, 6431, 7341, 7863, 426115, 453486, 1054067, 1054167, 1472746, 2017631, 42687015, 1050553507, 13175129925, 335038979077, 1400295262095, 5847307263801, 51722791547842, 78849864240621, 105802560494387

Offset

1,3

Links

Table of n, a(n) for n=1..23.

P. De Geest, Palindromic Octagonals

Mathematica

Select[Range[0, 10^5], PalindromeQ[PolygonalNumber[8, #]] &] (* Robert Price, Apr 29 2019 *)

Crossrefs

Cf. A057107, A000567.

Sequence in context: A340837 A121293 A246743 * A080973 A230882 A369089

Adjacent sequences: A057103 A057104 A057105 * A057107 A057108 A057109

Keyword

nonn,base

Author

Patrick De Geest, Aug 15 2000

Extensions

More terms from Herman Jamke (hermanjamke(AT)fastmail.fm), Apr 17 2008

a(1)=0 added by Robert Price, Apr 29 2019

Status

approved