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 A029962 Palindromic in bases 5 and 10. 39

%I

%S 0,1,2,3,4,6,88,252,282,626,676,1221,15751,18881,10088001,10400401,

%T 27711772,30322303,47633674,65977956,808656808,831333138,831868138,

%U 836131638,836181638,2512882152,2596886952,2893553982,6761551676

%N Palindromic in bases 5 and 10.

%H Robert G. Wilson v, <a href="/A029962/b029962.txt">Table of n, a(n) for n = 1..79</a>

%H P. De Geest, <a href="http://www.worldofnumbers.com/nobase10.htm">Palindromic numbers beyond base 10</a>

%t NextPalindrome[n_] := Block[{l = Floor[ Log[10, n] + 1], idn = IntegerDigits[n]}, If[ Union[idn] == {9}, Return[n + 2], If[l < 2, Return[n + 1], If[ FromDigits[ Reverse[ Take[idn, Ceiling[l/2]] ]] FromDigits[ Take[idn, -Ceiling[l/2]]], FromDigits[ Join[ Take[idn, Ceiling[l/2]], Reverse[ Take[idn, Floor[l/2]] ]]], idfhn = FromDigits[ Take[idn, Ceiling[l/2]]] + 1; idp = FromDigits[ Join[ IntegerDigits[idfhn], Drop[ Reverse[ IntegerDigits[idfhn]], Mod[l, 2]] ]]] ]]]; palQ[n_Integer, base_Integer] := Block[{idn = IntegerDigits[n, base]}, idn == Reverse[idn]]; l = {0}; a = 0; Do[a = NextPalindrome[a]; If[ palQ[a, 5], AppendTo[l, a]], {n, 200000}]; l (* _Robert G. Wilson v_, Sep 30 2004 *)

%t Select[Range[0, 10^5],

%t PalindromeQ[#] && # == IntegerReverse[#, 5] &] (* _Robert Price_, Nov 09 2019 *)

%Y Cf. A007632, A007633, A029961, A029963, A029964, A029965, A029966, A029967, A029968, A029969, A029970.

%K nonn,base

%O 1,3

%A _Patrick De Geest_

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Last modified December 9 09:33 EST 2019. Contains 329877 sequences. (Running on oeis4.)