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A029950 Odd palindromes. 4

%I

%S 1,3,5,7,9,11,33,55,77,99,101,111,121,131,141,151,161,171,181,191,303,

%T 313,323,333,343,353,363,373,383,393,505,515,525,535,545,555,565,575,

%U 585,595,707,717,727,737,747,757,767,777,787,797,909,919,929,939,949

%N Odd palindromes.

%C There are more odd palindromes (A328332) less than 10^K than even palindromes (A328333) because odd palindromes begin with 1, 3, 5, 7 or 9 while even palindromes begin only with 2, 4, 6 or 8. - _Bernard Schott_, Oct 24 2019

%H Philip Mizzi, <a href="/A029950/b029950.txt">Table of n, a(n) for n = 1..7110</a> (terms up to 20000000).

%H P. De Geest, <a href="http://www.worldofnumbers.com/index.html">World!Of Numbers</a>

%t palindromicQ[n_,b_:10]:=TrueQ[IntegerDigits[n, b]==Reverse[IntegerDigits[n, b]]];Select[Range[1, 10^4, 2], palindromicQ[#]&&Plus@@Drop[DigitCount[#], {1, 10, 1}]==0&] (* _Vincenzo Librandi_, Feb 07 2014 *)

%t Select[Range[1,949,2],PalindromeQ] (* Requires Mathematica version 10 or later *) (* _Harvey P. Dale_, Jul 15 2017 *)

%o (PARI) lista(nn) = {forstep(n=1, nn, 2, if (is_A002113(n), print1(n, ", ")));} \\ _Michel Marcus_, Feb 06 2014

%Y Subsequence of A002113.

%Y Cf. A029951 (even palindromes), A328332, A328333.

%K nonn,base

%O 1,2

%A _Patrick De Geest_

%E Offset set to 1 and more terms from _Michel Marcus_, Feb 06 2014

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Last modified August 8 02:45 EDT 2020. Contains 336290 sequences. (Running on oeis4.)