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A235110
Primes whose base-10 representation also represents a prime in base 13.
4
2, 3, 5, 7, 23, 41, 47, 61, 83, 89, 157, 173, 179, 197, 223, 229, 263, 281, 311, 313, 331, 373, 379, 397, 401, 463, 467, 487, 571, 599, 607, 643, 661, 739, 751, 773, 797, 809, 823, 863, 883, 919, 937, 971, 977
OFFSET
1,1
COMMENTS
See A090712 for a similar sequence whose definition works "in the opposite direction".
EXAMPLE
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.
MATHEMATICA
Select[Prime[Range[5000]], PrimeQ[FromDigits[IntegerDigits[#], 13]]&] (* Zak Seidov, Aug 31 2015 *)
PROG
(PARI) is_A235110(p, b=13)={my(d=digits(p)); isprime(vector(#d, i, b^(#d-i))*d~)&&isprime(p)}
CROSSREFS
Cf. A235110, A235144 and other sequences in the range A090707 - A091924.
Sequence in context: A155873 A362678 A106711 * A048398 A059170 A068710
KEYWORD
nonn,base
AUTHOR
M. F. Hasler, Jan 03 2014
STATUS
approved