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Numbers that are palindromic in bases 2 and 6.
17

%I #27 Oct 27 2014 20:45:54

%S 0,1,3,5,7,21,129,427,693,819,3999,4257,4593,28539,66433,85093,148617,

%T 151497,153513,180213,425971,1040319,1093281,1508381,1632995,1974031,

%U 1986127,30522135,30643095,208080483,1894216583,6662648163,8632935681

%N Numbers that are palindromic in bases 2 and 6.

%C Intersection of A006995 and A029953. - _Michel Marcus_, Oct 09 2014

%H Ray Chandler, <a href="/A182233/b182233.txt">Table of n, a(n) for n = 1..70</a> (terms < 10^18)

%e 85093 base 2 = 10100110001100101 and 85093 base 6 = 1453541.

%t b1 = 2; b2 = 6; lst = {}; Do[d1 = IntegerDigits[n, b1]; d2 = IntegerDigits[n, b2]; If[d1 == Reverse[d1] && d2 == Reverse[d2], AppendTo[lst, n]], {n, 2000000}]; lst (* _T. D. Noe_, Apr 19 2012 *)

%o (PARI) isok(n) = (d2=digits(n, 2)) && (d2==Vecrev(d2)) && (d6=digits(n, 6)) && (d6==Vecrev(d6)); \\ _Michel Marcus_, Oct 27 2014

%Y Cf. A006995 (base 2), A029953 (base 6).

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

%K nonn,base

%O 1,3

%A _Alex Ratushnyak_, Apr 19 2012

%E a(28)-a(33) and b-file from _Ray Chandler_, Oct 27 2014