A097929 - OEIS

%I #27 Oct 31 2014 15:14:36

%S 0,1,2,3,46,9222,76449,193662,2347506,2593206,17099841,17402241,

%T 25651017,32317933,16516113567,16619231967,155784877126,2806999337418,

%U 3101308506654,37004798195346,47470618709562,48517516968462

%N Numbers in base 10 that are palindromic in bases 4 and 5.

%C Intersection of A014192 and A029952. - _Michel Marcus_, Oct 09 2014

%H Ray Chandler, <a href="/A097929/b097929.txt">Table of n, a(n) for n = 1..26</a> (terms < 10^18)

%H Cino Hilliard, <a href="http://groups.msn.com/BC2LCC/page.msnw?fc_p=%2FPari%20GP%20scripts&amp;fc_a=0">util.gp PARI Functions not in the PARI Library</a>. [broken link]

%H Cino Hilliard, <a href="/A097928/a097928.txt">Pari Utilities (cached)</a>

%e 9222 base 10 is 2100012 base 4 and 9222 base 10 is 243342 base 5.

%t Do[ p4 = IntegerDigits[n, 4]; If[ FromDigits[ Reverse[ p4]] == FromDigits[p4], p5 = IntegerDigits[n, 5]; If[ FromDigits[ Reverse[p5]] == FromDigits[p5], Print[n]]], {n, 2*10^7}] (* _Robert G. Wilson v_, Sep 07 2004 *)

%o (PARI) /* Requires reading the util.gp file in the link into the gp session. */

%o palbase(n,b1,b2) = { for(x=1,n, if(ispal(base(10,b1,x))& ispal(base(10,b2,x)),print1(x",")) ) }

%Y Cf. A014192 (base 4), A029952 (base 5).

%K base,nonn

%O 1,3

%A _Cino Hilliard_, Sep 04 2004

%E More terms from _Robert G. Wilson v_, Sep 07 2004

%E a(15)-a(22) from _Donovan Johnson_, Apr 23 2010