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%I #32 Nov 02 2023 23:41:42
%S 2,3,5,7,29,53,59,79,107,113,241,263,269,293,367,373,419,443,521,523,
%T 547,601,607,631,677,757,761,787,937,971,1021,1069,1093,1231,1249,
%U 1277,1307,1361,1381,1433,1459,1543,1567,1613,1619,2213,2237,2239,2447,2477
%N Primes whose base-13 expansion is a (valid) decimal expansion of a prime.
%C See A235110 for a similar sequence whose definition works "in the opposite direction": Actually, the base-13 representation of the terms here. - _M. F. Hasler_, Jan 03 2014
%H Robert Price, <a href="/A090712/b090712.txt">Table of n, a(n) for n = 1..14473</a>
%e The prime p = 53 is written 41 in base 13, and 41 is again (the base 10 representation of) a prime. Therefore p = 53 is a term of this sequence. [Rephrased by _M. F. Hasler_, Jan 03 2014]
%t f[n_]:=Module[{c13=FromDigits[IntegerDigits[n],13]},If[PrimeQ[c13], c13,0]]; Select[f/@Prime[Range[500]],#!=0&] (* _Harvey P. Dale_, Jun 20 2011 *)
%o (PARI) is_A090712(p)=vecmax(d=digits(p,13))<10&&isprime(vector(#d,i,10^(#d-i))*d~)&&isprime(p) \\ _M. F. Hasler_, Jan 05 2014
%Y Cf. A090707 - A091924.
%K base,nonn
%O 1,1
%A _Cino Hilliard_, Jan 18 2004
%E Edited by _N. J. A. Sloane_, Feb 07 2007, and by _M. F. Hasler_, Jan 05 2014
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