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%I #8 Nov 24 2015 01:42:15
%S 2,3,23,47,53,61,67,71,89,127,137,191,397,443,701,1031,1117,1223,1499,
%T 1549,1579,1621,1699,1933,1951,2129,2207,2311,2381,2473,2521,2671,
%U 2731,2753,2833,3011,3019,3061,3967,4051,4093,4127,4229,4397,4457,4943,5023
%N {3,7}-primes (defined in Comments).
%C 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)).
%H Clark Kimberling, <a href="/A262838/b262838.txt">Table of n, a(n) for n = 1..1000</a>
%t {b1, b2} = {3, 7};
%t u = Select[Prime[Range[6000]], PrimeQ[FromDigits[IntegerDigits[#, b1], b2]] &]; (* A231477 *)
%t v = Select[Prime[Range[6000]], PrimeQ[FromDigits[IntegerDigits[#, b2], b1]] &]; (* A262837 *)
%t w = Intersection[u, v]; (* A262838 *)
%t (* _Peter J. C. Moses_, Sep 27 2015 *)
%Y Cf. A000040, A231477, A262837, A262829.
%K nonn,easy,base
%O 1,1
%A _Clark Kimberling_, Nov 09 2015
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