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A178318 Primes which remain prime after reflection across a vertical line through the middle of the number (numbers are written as digital clock style numerals).

%I A178318 #5 Jul 16 2014 15:40:20
%S A178318 2,5,11,101,181,1051,1181,1201,1811,10151,11251,11551,12101,12211,
%T A178318 12511,15121,18181,100151,100501,101501,101581,102001,102101,102181,
%U A178318 102551,105211,105251,108881,110051,110581,110881,111521,111581,115021,115201
%N A178318 Primes which remain prime after reflection across a vertical line through the middle of the number (numbers are written as digital clock style numerals).
%C A178318 Apart from first two terms: subsequence of A208259. - _Reinhard Zumkeller_, Jul 16 2014
%H A178318 Reinhard Zumkeller, <a href="/A178318/b178318.txt">Table of n, a(n) for n = 1..1000</a>
%e A178318 For example 1051 becomes 1201 under this reflection and since these are both prime, these number are part of the sequence. Note that a number must be composed only of the digits 0,1,2,5,8 to qualify.
%o A178318 (Haskell)
%o A178318 import Data.List (intersect, genericIndex)
%o A178318 a178318 n = a178318_list !! (n-1)
%o A178318 a178318_list = 2 : 5 : filter f a062332_list where
%o A178318    f p = null (show p `intersect` "34679") && a010051' (r 0 p) == 1
%o A178318    r y 0 = y
%o A178318    r y x = r (10 * y + genericIndex [0,1,5,0,0,2,0,0,8,0] d) x'
%o A178318              where (x', d) = divMod x 10
%o A178318 -- _Reinhard Zumkeller_, Jul 16 2014
%Y A178318 Cf. A125308, A178317.
%Y A178318 Cf. A010051, A004086, A208259, A062332.
%K A178318 nonn,base
%O A178318 1,1
%A A178318 _David Nacin_, May 24 2010