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%I #28 Jul 02 2024 08:23:37
%S 3,5,7,11,13,71,73,149,151,179,181,311,313,1031,1033,1151,1153,1229,
%T 1231,3299,3301,3371,3373,3389,3391,3467,3469,3851,3853,7457,7459,
%U 7949,7951,9011,9013,9437,9439,10007,10009,10067,10069,10457,10459,10499,10501,10889
%N Twin primes where both the prime and its twin have prime reversals.
%H Robert Israel, <a href="/A373349/b373349.txt">Table of n, a(n) for n = 1..10001</a>
%p R:= n-> (s-> parse(cat(s[-i]$i=1..length(s))))(""||n):
%p q:= p-> andmap(isprime, [p, R(p)]) and ormap(
%p t-> andmap(isprime, [p+t, R(p+t)]), [-2, +2]):
%p select(q, [$2..12000])[]; # _Alois P. Heinz_, Jun 06 2024
%o (PARI) isrevp(p) = isprime(p) && isprime(fromdigits(Vecrev(digits(p))));
%o isok(p) = isprime(p) && ((isprime(p+2) && isrevp(p+2)) || (isprime(p-2) && isrevp(p-2))) && isrevp(p); \\ _Michel Marcus_, Jun 06 2024
%Y Cf. A001097, A007500.
%Y Cf. A004086.
%K nonn,base
%O 1,1
%A _Thomas Otten_, Jun 01 2024
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