A046232 Cubes which are palindromes in base 4.

0, 1, 125, 4913, 274625, 16974593, 1076890625, 68769820673, 4398851866625, 281487861809153, 18014604668698625, 1152924803144876033, 73787029071408922625, 4722367327294625677313, 302231468414456377114625, 19342813330006849714388993, 1237940042744144791940890625, 79228162569604569827557507073

Offset

1,3

Links

Table of n, a(n) for n=1..18.

Patrick De Geest, World!Of Numbers, Palindromic cubes in bases 2 to 17.

Formula

It seems that a(n+2) = 64^n + 3*16^n + 3*4^n + 1 for n > 0.

Conjectured g.f.: x^2*(1 + 40*x - 4284*x^2 + 30080*x^3 - 28672*x^4)/((1 - x)*(1 - 4*x)*(1 - 16*x)*(1 - 64*x)). - Stefano Spezia, Jul 31 2022

Crossrefs

Cf. A020531, A046231.

Sequence in context: A265931 A265477 A017583 * A102076 A223229 A030695

Adjacent sequences: A046229 A046230 A046231 * A046233 A046234 A046235

Keyword

nonn,base

Author

Patrick De Geest, May 15 1998

Extensions

Offset changed to 1 by Stefano Spezia, Jul 31 2022

More terms using A046231 added by Michel Marcus, Aug 02 2022

Status

approved