A160748 - OEIS

A160748

Primes whose digits are primes and reverse is prime.

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

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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-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

Adjacent sequences: A160745 A160746 A160747 * A160749 A160750 A160751

KEYWORD

nonn,base

AUTHOR

Vincenzo Librandi, Jan 24 2010

STATUS

approved