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A259377 Palindromic numbers in bases 3 and 7 written in base 10.

%I A259377 #20 Aug 18 2015 12:57:29
%S A259377 0,1,2,4,8,16,40,100,121,142,164,242,328,400,1312,8200,9103,14762,
%T A259377 54008,76024,108016,112048,233920,532900,639721,741586,2585488,
%U A259377 3316520,11502842,24919360,35664908,87001616,184827640,4346524576,5642510512,11641189600,65304259157,68095147754,469837033600,830172165614,17136683996456,21772277941544,22666883572232,45221839119556
%N A259377 Palindromic numbers in bases 3 and 7 written in base 10.
%H A259377 Giovanni Resta, <a href="/A259377/b259377.txt">Table of n, a(n) for n = 1..72</a>
%H A259377 <a href="/index/Pac#palindromes">Index entries for sequences related to palindromes</a>
%F A259377 Intersection of A014190 and A029954.
%e A259377 142 is in the sequence because 142_10 = 262_7 = 12021_3.
%t A259377 (* 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, 7]; If[palQ[pp, 3], AppendTo[lst, pp]; Print[pp]]; k++]; lst
%t A259377 b1=3; b2=7; 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 A259377 Cf. A007632,  A007633, A029731, A029804, A029961, A029962, A029963, A029964, A029965, A029966, A029967, A029968, A029969, A029970, A048268, A060792, A097855, A097856, A097928, A097929, A097930, A097931, A099145, A099146, A099165, A182232, A182233, A182234, A250408, A250409, A250410, A250411, A250412, A259374, A259375, A259376, A259377, A259378, A249156, A259380, A259381, A259382, A259383, A259384, A259385, A259386, A259387, A259388, A259389, A259390.
%K A259377 nonn,base
%O A259377 1,3
%A A259377 Eric A. Schmidt and _Robert G. Wilson v_, Jul 16 2015