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A160748 Primes whose digits are primes and reverse is prime.

%I A160748 #15 Sep 08 2022 08:45:45
%S A160748 2,3,5,7,37,73,337,353,373,727,733,757,3257,3373,3527,3733,7253,7523,
%T A160748 7577,7757,32233,32257,32323,32353,32377,32537,33223,33533,35227,
%U A160748 35257,35323,35327,35353,35537,35753,37273,37573,72227,72253,72337,72353
%N A160748 Primes whose digits are primes and reverse is prime.
%C A160748 Intersection of A007500 and A019546. - _Michel Marcus_, Dec 04 2015
%H A160748 Robert Israel, <a href="/A160748/b160748.txt">Table of n, a(n) for n = 1..8096</a>
%p A160748 listtoint:= proc(L) local i; add(L[i]*10^(i-1),i=1..nops(L)) end proc:
%p A160748 f:= proc(L) local s;
%p A160748   s:= listtoint(L);
%p A160748   if isprime(s) and isprime(listtoint(ListTools:-Reverse(L))) then s fi
%p A160748 end proc:
%p A160748 Cands:= [[3],[7]]:
%p A160748 A:= 2,3,5,7:
%p A160748 for m from 2 to 6 do
%p A160748   Cands:= map(t -> seq([op(t),j], j=[2,3,5,7]), Cands);
%p A160748   A:= A, op(sort(map(f,Cands)));
%p A160748 od:
%p A160748 A; # _Robert Israel_, Dec 04 2015
%t A160748 okQ[p_] := PrimeQ[IntegerReverse[p] && AllTrue[IntegerDigits[p], PrimeQ]];
%t A160748 Select[Prime[Range[10^4]], okQ] (* _Jean-François Alcover_, Feb 06 2018 *)
%o A160748 (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
%Y A160748 Cf. A007500 (reversible primes), A019546 (primes with prime digits).
%K A160748 nonn,base
%O A160748 1,1
%A A160748 _Vincenzo Librandi_, Jan 24 2010