A235110 Primes whose base-10 representation also represents a prime in base 13.

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".

Links

Zak Seidov, Table of n, a(n) for n = 1..10000

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

Adjacent sequences: A235107 A235108 A235109 * A235111 A235112 A235113

Keyword

nonn,base

Author

M. F. Hasler, Jan 03 2014

Status

approved