A182234 Numbers that are palindromic in bases 2 and 7.

0, 1, 3, 5, 85, 107, 257, 5049, 9201, 11253, 11757, 210099, 399171, 512607, 786435, 12916899, 19992857, 22468309, 1052109663, 15935958711, 24051338445, 37344016593, 71859215265, 72822171105, 1566399158893, 3425211644643

Offset

1,3

Comments

Intersection of A006995 and A029954. - Michel Marcus, Oct 09 2014

Links

Ray Chandler, Table of n, a(n) for n = 1..31 (terms < 10^18)

Example

786435 base 2 = 11000000000000000011 and 786435 base 7 = 6453546.

Mathematica

b1 = 2; b2 = 7; lst = {}; Do[d1 = IntegerDigits[n, b1]; d2 = IntegerDigits[n, b2]; If[d1 == Reverse[d1] && d2 == Reverse[d2], AppendTo[lst, n]], {n, 1000000}]; lst (* T. D. Noe, Apr 19 2012 *)

Crossrefs

Cf. A006995 (base 2), A029954 (base 7).

Cf. A060792 (base 2 and 3), A097856 (base 2 and 4).

Sequence in context: A144617 A301492 A107655 * A308612 A082715 A133660

Adjacent sequences: A182231 A182232 A182233 * A182235 A182236 A182237

Keyword

nonn,base

Author

Alex Ratushnyak, Apr 19 2012

Extensions

a(19)-a(28) from Donovan Johnson, Apr 27 2012

b-file to 31 terms from Ray Chandler, Oct 27 2014

Status

approved