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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
OFFSET
1,1
COMMENTS
Intersection of A007500 and A019546. - Michel Marcus, Dec 04 2015
LINKS
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-François 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 A352023
KEYWORD
nonn,base
AUTHOR
Vincenzo Librandi, Jan 24 2010
STATUS
approved