A090712 -id:A090712 - cp's OEIS frontend

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

M. F. Hasler, Jan 03 2014

See A090712 for a similar sequence whose definition works "in the opposite direction".

			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.

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

Cf. A235110, A235144 and other sequences in the range A090707 - A091924.

Select[Prime[Range[5000]],PrimeQ[FromDigits[IntegerDigits[#],13]]&] (* Zak Seidov, Aug 31 2015 *)

is_A235110(p, b=13)={my(d=digits(p)); isprime(vector(#d, i, b^(#d-i))*d~)&&isprime(p)}

A090711 Primes whose base-11 expansion is a (valid) decimal expansion of a prime.

Original entry on oeis.org

2, 3, 5, 7, 31, 47, 67, 73, 97, 163, 223, 227, 229, 271, 311, 317, 331, 397, 421, 443, 449, 557, 683, 727, 733, 773, 883, 953, 977, 991, 997, 1063, 1109, 1129, 1367, 1373, 1433, 1483, 1607, 1613, 1637, 1657, 1697, 1723, 1783, 1871, 1873, 1879, 2027, 2203, 2269

Offset: 1

Cino Hilliard, Jan 18 2004

See A091924 for the sequence whose definition works "the other way round": Actually, the base-11 representation of the terms of this sequence here. - M. F. Hasler, Jan 03 2014

			The prime p = 31 is written 29 in base 11, and 29 read in base 10 is again a prime. So 31 is a term.

Robert Price, Table of n, a(n) for n = 1..19838

Cf. A090712.

b11pQ[n_]:=Module[{d=IntegerDigits[n,11]},Max[d]<10&&PrimeQ[FromDigits[ d]]]; Select[Prime[Range[400]],b11pQ] (* Harvey P. Dale, Apr 17 2018 *)

is(p,b=10,c=11)=vecmax(d=digits(p,c))M. F. Hasler, Jan 05 2014

Edited by N. J. A. Sloane, Feb 07 2007, and by M. F. Hasler, Jan 03 2014

cp's OEIS Frontend

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

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