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Palindromic primes starting with a digit 7.
3

%I #6 Nov 22 2022 19:52:53

%S 7,727,757,787,797,70207,70507,70607,71317,71917,72227,72727,73037,

%T 73237,73637,74047,74747,75557,76367,76667,77377,77477,77977,78487,

%U 78787,78887,79397,79697,79997,7014107,7035307,7036307,7041407,7046407,7057507,7065607,7069607

%N Palindromic primes starting with a digit 7.

%C Subsequence of A002385 (palindromic primes) and A002113 (palindromic numbers). Complement of A222728 (palindromic composite numbers starting with a digit 7) with respect to A043042 (palindromic numbers starting with a digit 7).

%H Jaroslav Krizek, <a href="/A222727/b222727.txt">Table of n, a(n) for n = 1..1000</a>

%t Select[Prime[Range[500000]],PalindromeQ[#]&&Mod[#,10]==7&] (* _Harvey P. Dale_, Nov 22 2022 *)

%Y Cf. A002385, A002113, A222728, A043042.

%K nonn,base

%O 1,1

%A _Jaroslav Krizek_, Mar 09 2013