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%I #10 Sep 08 2022 08:46:08
%S 2,5,7,11,13,17,19,29,31,37,43,53,59,61,67,71,73,79,97,101,103,107,
%T 109,113,127,131,137,139,149,151,157,163,167,173,179,181,191,193,197,
%U 199,211,223,227,229,239,241,263,269,271,277,283,293,307,311,313,317,331
%N Primes p such that (p reversed)-1 is not a prime.
%C Complement of A167216.
%H Andrew Howroyd, <a href="/A245063/b245063.txt">Table of n, a(n) for n = 1..1000</a>
%t Select[Prime[Range[3700]], ! PrimeQ[FromDigits[Reverse[IntegerDigits[#]]] - 1] &]
%o (Magma) [p: p in PrimesInInterval(2, 400) |not IsPrime(q-1) where q is Seqint(Reverse(Intseq(p)))];
%o (PARI) ok(n)={isprime(n)&&!isprime(fromdigits(Vecrev(digits(n)))-1)} \\ _Andrew Howroyd_, Feb 27 2018
%Y Cf. A167216.
%K nonn,base
%O 1,1
%A _Vincenzo Librandi_, Jul 11 2014
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