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A262833
(7,2)-primes (defined in Comments).
3
2, 3, 5, 7, 17, 31, 43, 47, 61, 71, 73, 89, 101, 103, 113, 127, 157, 173, 197, 199, 229, 239, 241, 269, 271, 281, 311, 337, 353, 367, 379, 383, 397, 409, 439, 449, 463, 479, 509, 521, 577, 607, 617, 631, 647, 661, 673, 677, 719, 743, 761, 827, 857, 887, 911
OFFSET
1,1
COMMENTS
Let V = (b(1), b(2), ..., b(k)), where k > 1 and b(i) are distinct integers > 1 for j = 1..k. Call p a V-prime if the digits of p in base b(1) spell a prime in each of the bases 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 01 2015
STATUS
approved