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A262834
{2,7}-primes (defined in Comments).
2
2, 31, 47, 103, 173, 199, 229, 367, 409, 463, 743, 827, 911, 967, 1123, 1163, 1321, 1447, 1583, 1657, 1669, 2161, 2647, 2677, 2861, 3361, 3673, 3851, 4079, 4231, 4271, 4513, 4663, 5003, 5381, 5923, 6329, 6569, 7043, 7103, 7393, 7561, 8263, 8753, 9649, 10337
OFFSET
1,1
COMMENTS
Let S = {b(1), b(2), ..., b(k)}, where k > 1 and b(i) are distinct integers > 1 for j = 1..k. Call p an S-prime if the digits of p in base b(i) spell a prime in each of the bases b(j) in S, for i = 1..k. Equivalently, p is an S-prime if p is a strong-V prime (defined at A262729) for every permutation of the vector V = (b(1), b(2), ..., b(k)).
LINKS
MATHEMATICA
{b1, b2} = {2, 7};
u = Select[Prime[Range[6000]], PrimeQ[FromDigits[IntegerDigits[#, b1], b2]] &]; (* A235477 *)
v = Select[Prime[Range[6000]], PrimeQ[FromDigits[IntegerDigits[#, b2], b1]] &]; (* A262833 *)
w = Intersection[u, v]; (* A262834 *)
(* Peter J. C. Moses, Sep 27 2015 *)
CROSSREFS
KEYWORD
nonn,easy,base
AUTHOR
Clark Kimberling, Nov 05 2015
STATUS
approved