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%I #13 Jul 03 2018 05:43:42
%S 3,5,7,11,13,17,19,23,31,37,43,47,53,59,67,71,73,79,83,97,101,103,107,
%T 109,113,127,131,137,139,149,151,157,163,167,173,179,181,191,193,197,
%U 199,211,223,227,263,271,283,307,311,313,317,331,337,347,353,359,367,373,379,397,419,431,443,463,467,479,487,503,509,523
%N Primes which remain prime after all even digits are removed.
%C Obviously all primes with just odd digits are members of this sequence.
%e 23 is a member because if the digit 2 is removed the resulting number becomes 3 which is a prime.
%t Select[Prime@ Range@ 100, PrimeQ[ FromDigits[ Select[ IntegerDigits@#, OddQ]]] &]
%o (PARI) isok(p) = isprime(p) && isprime(fromdigits(select(x->(x % 2), digits(p)))); \\ _Michel Marcus_, Jun 21 2018
%Y Cf. A030096 (subsequence), A306085, A306086.
%K nonn,base
%O 1,1
%A _Zak Seidov_ and _Robert G. Wilson v_, Jun 20 2018
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