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A318568 Primes p such that 2^p reversed is a prime. 0
5, 7, 17, 37, 107, 137, 271 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Equivalently, primes in A057708. - Muniru A Asiru, Dec 25 2018

LINKS

Table of n, a(n) for n=1..7.

MATHEMATICA

Select[Prime[Range[100]], PrimeQ[ToExpression[StringReverse[ToString[2^#]]]] &]

PROG

(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

CROSSREFS

Cf. A059706.

Subsequence of A057708.

Sequence in context: A018538 A038968 A243400 * A239414 A163570 A113282

Adjacent sequences:  A318565 A318566 A318567 * A318569 A318570 A318571

KEYWORD

nonn,base,more

AUTHOR

Vincenzo Librandi, Sep 22 2018

STATUS

approved

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Last modified November 19 20:42 EST 2019. Contains 329323 sequences. (Running on oeis4.)