login
A057107
Octagonal palindromes.
5
0, 1, 8, 8008, 120232021, 124060421, 161656161, 185464581, 544721127445, 616947749616, 3333169613333, 3333802083333, 6506939396056, 12212500521221, 5466543663456645, 3310988011108890133, 520752145595541257025, 336753352502205253357633
OFFSET
1,3
LINKS
MATHEMATICA
Select[PolygonalNumber[8, Range[0, 10^5]], PalindromeQ] (* Robert Price, Apr 29 2019 *)
CROSSREFS
Sequence in context: A090494 A079656 A114773 * A320864 A052152 A189250
KEYWORD
nonn,base
AUTHOR
Patrick De Geest, Aug 15 2000
EXTENSIONS
a(1)=0 added by Robert Price, Apr 29 2019
STATUS
approved