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A262831 (5,2)-primes (defined in Comments). 2

%I #9 Mar 03 2024 09:29:44

%S 2,3,5,11,13,23,31,41,43,53,61,71,73,83,101,103,113,131,151,163,173,

%T 181,191,223,233,241,251,263,281,293,311,313,331,373,383,401,421,433,

%U 443,461,463,491,521,523,541,563,593,631,641,653,673,683,691,701,733

%N (5,2)-primes (defined in Comments).

%C 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).

%H Clark Kimberling, <a href="/A262831/b262831.txt">Table of n, a(n) for n = 1..10000</a>

%t {b1, b2} = {2, 5};

%t u = Select[Prime[Range[6000]], PrimeQ[FromDigits[IntegerDigits[#, b1], b2]] &];

%t (* A235475 *)

%t v = Select[Prime[Range[6000]], PrimeQ[FromDigits[IntegerDigits[#, b2], b1]] &];

%t (* A262831 *)

%t w = Intersection[u, v]; (* A262832 *)

%t (* _Peter J. C. Moses_, Sep 27 2015 *)

%Y Cf. A000040, A262729, A262832, A262833.

%K nonn,easy,base

%O 1,1

%A _Clark Kimberling_, Oct 31 2015

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Last modified April 20 00:26 EDT 2024. Contains 371798 sequences. (Running on oeis4.)