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A160748 Primes whose digits are primes and reverse is prime. 1
2, 3, 5, 7, 37, 73, 337, 353, 373, 727, 733, 757, 3257, 3373, 3527, 3733, 7253, 7523, 7577, 7757, 32233, 32257, 32323, 32353, 32377, 32537, 33223, 33533, 35227, 35257, 35323, 35327, 35353, 35537, 35753, 37273, 37573, 72227, 72253, 72337, 72353 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Intersection of A007500 and A019546. - Michel Marcus, Dec 04 2015

LINKS

Robert Israel, Table of n, a(n) for n = 1..8096

MAPLE

listtoint:= proc(L) local i; add(L[i]*10^(i-1), i=1..nops(L)) end proc:

f:= proc(L) local s;

  s:= listtoint(L);

  if isprime(s) and isprime(listtoint(ListTools:-Reverse(L))) then s fi

end proc:

Cands:= [[3], [7]]:

A:= 2, 3, 5, 7:

for m from 2 to 6 do

  Cands:= map(t -> seq([op(t), j], j=[2, 3, 5, 7]), Cands);

  A:= A, op(sort(map(f, Cands)));

od:

A; # Robert Israel, Dec 04 2015

MATHEMATICA

okQ[p_] := PrimeQ[IntegerReverse[p] && AllTrue[IntegerDigits[p], PrimeQ]];

Select[Prime[Range[10^4]], okQ] (* Jean-Fran├žois Alcover, Feb 06 2018 *)

PROG

(MAGMA) [p: p in PrimesUpTo(2*10^5) | Set(Intseq(p)) subset [2, 3, 5, 7] and IsPrime(Seqint(Reverse(Intseq(p))))]; // Vincenzo Librandi, Dec 04 2015

CROSSREFS

Cf. A007500 (reversible primes), A019546 (primes with prime digits).

Sequence in context: A048401 A288718 A289861 * A117639 A202263 A153014

Adjacent sequences:  A160745 A160746 A160747 * A160749 A160750 A160751

KEYWORD

nonn,base

AUTHOR

Vincenzo Librandi, Jan 24 2010

STATUS

approved

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Last modified February 15 22:28 EST 2019. Contains 320138 sequences. (Running on oeis4.)