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Palindromic primes with middle digit 6.
1

%I #17 Feb 14 2025 14:22:01

%S 10601,16661,70607,73637,76667,79697,94649,98689,1126211,1186811,

%T 1196911,1276721,1286821,1456541,1486841,1496941,1556551,1616161,

%U 1646461,1826281,1856581,1876781,1936391,1976791,3016103,3026203

%N Palindromic primes with middle digit 6.

%H Harvey P. Dale, <a href="/A082442/b082442.txt">Table of n, a(n) for n = 1..400</a>

%t Select[Prime[Range[220000]],OddQ[IntegerLength[#]]&&PalindromeQ[#]&&IntegerDigits[#][[(IntegerLength[#]+1)/2]]==6&] (* _Harvey P. Dale_, Feb 14 2025 *)

%o (Magma) [ p: p in PrimesUpTo(200000000) | IsOdd(d) and D[(d+1) div 2] eq 6 and D eq Reverse(D) where d is #D where D is Intseq(p) ]; // _Vincenzo Librandi_, Apr 12 2011

%Y Cf. A002385.

%K nonn,base,changed

%O 1,1

%A _Lekraj Beedassy_, Apr 25 2003

%E Corrected by _David Wasserman_, Sep 09 2004