A054970 Index numbers for palindromic hexagonal numbers.

0, 1, 2, 6, 39, 55, 87, 182, 556, 644, 797, 917, 1593, 1685, 25141, 51425, 55556, 83527, 810311, 1620213, 1853942, 5555556, 17352586, 17835196, 25004441, 91071921, 170563673, 181737182, 184252876, 507354403, 1240058219, 1783816196, 2756800387

Offset

1,3

Links

Table of n, a(n) for n=1..33.

Mathematica

Select[Range[0, 10^6], PalindromeQ[PolygonalNumber[6, #]] &] (* Robert Price, Apr 27 2019 *)

Crossrefs

Cf. A000384, A054969, A082721.

Sequence in context: A072191 A118324 A060421 * A211348 A295912 A120492

Adjacent sequences: A054967 A054968 A054969 * A054971 A054972 A054973

Keyword

nonn,base

Author

Jeff Heleen, May 26 2000

Extensions

Added a(1)=0 by Robert Price, Apr 27 2019

Status

approved