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A321523 List of pairs: primes whose reversal is also prime, each followed by its reversal.

%I A321523 #45 Dec 01 2018 09:41:43
%S A321523 2,2,3,3,5,5,7,7,11,11,13,31,17,71,31,13,37,73,71,17,73,37,79,97,97,
%T A321523 79,101,101,107,701,113,311,131,131,149,941,151,151,157,751,167,761,
%U A321523 179,971,181,181,191,191,199,991,311,113,313,313,337,733,347,743,353,353
%N A321523 List of pairs: primes whose reversal is also prime, each followed by its reversal.
%F A321523 a(2n-1) = A007500(n).
%F A321523 a(2n) = A004086(A007500(n)).
%F A321523 a(2n) = A095180(n). - _Rémy Sigrist_, Nov 16 2018
%e A321523 The sequence begins:
%e A321523      2,  2;
%e A321523      3,  3;
%e A321523      5,  5;
%e A321523      7,  7;
%e A321523     11, 11;
%e A321523     13, 31;
%e A321523     17, 71;
%e A321523     31, 13;
%e A321523     37, 73;
%e A321523     71, 17;
%e A321523 ...
%e A321523 107 has its reversal as 701.
%e A321523 971 has its reversal as 179.
%t A321523 Flatten@ Table[ If[PrimeQ[r = IntegerReverse@ p], {p,r}, {}], {p, Prime@ Range@ 71}] (* _Giovanni Resta_, Nov 13 2018 *)
%o A321523 (PARI) forprime(p=1, 353, r=fromdigits(Vecrev(digits(p))); if (isprime(r), print1(p ", " r ", "))) \\ _Rémy Sigrist_, Nov 16 2018
%Y A321523 Subsequence of A135020.
%Y A321523 Cf. A000040, A004086, A007500, A095180, A180022.
%K A321523 nonn,base,tabf
%O A321523 1,1
%A A321523 _Kritsada Moomuang_, Nov 12 2018