%I #11 Aug 18 2015 12:57:29

%S 0,1,2,3,5,10,255,273,373,546,2550,2730,2910,16319,23205,54215,

%T 1181729,1898445,2576758,3027758,3080174,4210945,9971750,163490790,

%U 2299011170,6852736153,6899910553,160142137430,174913133450,204283593150,902465909895,1014966912315,2292918574418,9295288254930,11356994802010,11372760382810,38244097345762

%N Palindromic numbers in bases 4 and 9 written in base 10.

%H Giovanni Resta, <a href="/A259387/b259387.txt">Table of n, a(n) for n = 1..57</a>

%H <a href="/index/Pac#palindromes">Index entries for sequences related to palindromes</a>

%F Intersection of A014192 and A029955.

%e 273 is in the sequence because 273_10 = 333_9 = 10101_4.

%t (* first load nthPalindromeBase from A002113 *) palQ[n_Integer, base_Integer] := Block[{}, Reverse[ idn = IntegerDigits[n, base]] == idn]; k = 0; lst = {}; While[k < 21000000, pp = nthPalindromeBase[k, 9]; If[palQ[pp, 4], AppendTo[lst, pp]; Print[pp]]; k++]; lst

%t b1=4; b2=9; lst={}; Do[d1=IntegerDigits[n, b1]; d2=IntegerDigits[n, b2]; If[d1==Reverse[d1]&&d2==Reverse[d2], AppendTo[lst, n]], {n, 0, 10000000}]; lst (* _Vincenzo Librandi_, Jul 17 2015 *)

%Y Cf. A048268, A060792, A097856, A097928, A182232, A259374, A097929, A182233, A259375, A259376,

%Y A097930, A182234, A259377, A259378, A249156, A097931, A259380, A259381, A259382, A259383,

%Y A259384, A099145, A259385, A259386, A259387, A259388, A259389, A259390, A099146, A007632,

%Y A007633, A029961, A029962, A029963, A029964, A029804, A029965, A029966, A029967, A029968,

%Y A029969, A029970, A029731, A097855, A250408, A250409, A250410, A250411, A099165, A250412.

%K nonn,base

%O 1,3

%A Eric A. Schmidt and _Robert G. Wilson v_, Jul 16 2015