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Numbers in base 10 that are palindromic in bases 3 and 4.
25

%I #25 Oct 31 2014 15:03:42

%S 0,1,2,10,130,11950,175850,749470,1181729,11435450,916821671,

%T 956613659,1136307905,46746179770,77887660577,635913760790,

%U 53903615484947,55988454554339,534479689454189,1956592840355065

%N Numbers in base 10 that are palindromic in bases 3 and 4.

%C Intersection of A014190 and A014192. - _Michel Marcus_, Oct 09 2014

%H Ray Chandler, <a href="/A097928/b097928.txt">Table of n, a(n) for n = 1..27</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 175850 base 10 is 22221012222 base 3 and 175850 base 10 is 222323222 base 4.

%t Do[ p3 = IntegerDigits[n, 3]; If[ FromDigits[ Reverse[ p3]] == FromDigits[p3], p4 = IntegerDigits[n, 4]; If[ FromDigits[ Reverse[p4]] == FromDigits[p4], Print[n]]], {n, 2*10^7}] (* _Robert G. Wilson v_, Sep 07 2004 *)

%o (PARI) palbase(n,b1,b2) = { for(x=1,n, if(ispal(base(10,b1,x))& ispal(base(10,b2,x)),print1(x",")) ) } \\Requires reading the util.gp file in the link into the gp session. Place in the \.gprc file to automate.

%Y Cf. A014190 (base 3), A014192 (base 4).

%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(11)-a(21) from _Donovan Johnson_, Apr 23 2010