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%I #14 Sep 01 2015 14:12:33
%S 2,3,5,7,23,41,47,61,83,89,157,173,179,197,223,229,263,281,311,313,
%T 331,373,379,397,401,463,467,487,571,599,607,643,661,739,751,773,797,
%U 809,823,863,883,919,937,971,977
%N Primes whose base-10 representation also represents a prime in base 13.
%C See A090712 for a similar sequence whose definition works "in the opposite direction".
%H Zak Seidov, <a href="/A235110/b235110.txt">Table of n, a(n) for n = 1..10000</a>
%e The decimal representation of prime 23, considered as a number written in base 13, stands for 2*13+3 = 29, which is also prime, therefore 23 is in the sequence.
%t Select[Prime[Range[5000]],PrimeQ[FromDigits[IntegerDigits[#],13]]&] (* _Zak Seidov_, Aug 31 2015 *)
%o (PARI) is_A235110(p, b=13)={my(d=digits(p)); isprime(vector(#d, i, b^(#d-i))*d~)&&isprime(p)}
%Y Cf. A235110, A235144 and other sequences in the range A090707 - A091924.
%K nonn,base
%O 1,1
%A _M. F. Hasler_, Jan 03 2014
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