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A318568
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Primes p such that 2^p reversed is a prime.
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0
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OFFSET
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1,1
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COMMENTS
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LINKS
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MATHEMATICA
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Select[Prime[Range[100]], PrimeQ[ToExpression[StringReverse[ToString[2^#]]]] &]
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PROG
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(Magma) [p: p in PrimesUpTo(200) | IsPrime(Seqint(Reverse(Intseq(2^p))))];
(PARI) isok(p) = isprime(p) && isprime(fromdigits(Vecrev(digits(2^p)))); \\ Michel Marcus, Sep 22 2018
(GAP) P0:=List(List([1..300], j->Reversed(ListOfDigits(2^j))), k->Sum([1..Size(k)], i->k[i]*10^(Size(k)-i)));;
a:=Filtered([1..Length(P0)], m->IsPrime(m) and IsPrime(P0[m]));; Print(a); # Muniru A Asiru, Dec 25 2018
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CROSSREFS
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KEYWORD
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nonn,base,more
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AUTHOR
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STATUS
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approved
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