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A262840 {5,7}-primes (defined in Comments). 2
2, 3, 5, 13, 17, 23, 41, 43, 53, 71, 79, 101, 137, 157, 181, 191, 239, 281, 379, 463, 743, 839, 863, 967, 1151, 1171, 1303, 1367, 1663, 1721, 2083, 2251, 2297, 2351, 2621, 2659, 2957, 2999, 3257, 3343, 3373, 3511, 3607, 3767, 3863, 3877, 3907, 4217, 4447 (list; graph; refs; listen; history; text; internal format)
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

Clark Kimberling, Table of n, a(n) for n = 1..5000

MATHEMATICA

{b1, b2} = {5, 7};

u = Select[Prime[Range[6000]], PrimeQ[FromDigits[IntegerDigits[#, b1], b2]] &];  (* A235635 *)

v = Select[Prime[Range[6000]], PrimeQ[FromDigits[IntegerDigits[#, b2], b1]] &];  (* A262839 *)

w = Intersection[u, v]; (* A262840 *)

(* Peter J. C. Moses, Sep 27 2015 *)

CROSSREFS

Cf. A000040, A235635, A262839, A262829.

Sequence in context: A235635 A253645 A214802 * A215318 A186945 A193761

Adjacent sequences:  A262837 A262838 A262839 * A262841 A262842 A262843

KEYWORD

nonn,easy,base

AUTHOR

Clark Kimberling, Nov 09 2015

STATUS

approved

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Last modified December 10 23:33 EST 2018. Contains 318049 sequences. (Running on oeis4.)