A246043 Biprimatic permutable numbers: Decimal numbers whose digits can be arranged to form exactly two prime numbers. No leading zeros.

13, 17, 31, 37, 71, 73, 79, 97, 107, 118, 119, 124, 125, 127, 128, 133, 139, 142, 146, 152, 164, 169, 170, 172, 181, 182, 191, 193, 196, 214, 215, 217, 218, 238, 239, 241, 251, 271, 277, 281, 283, 293, 313, 319, 328, 329, 331, 346, 347, 349, 356, 364, 365, 367, 368, 374, 376, 382, 386, 391, 392, 394, 412, 416, 421, 436, 437

Offset: 1

Author

Andreas Boe, Aug 23 2014

Keywords

• nonn
• base

Comments

In base ten these numbers can be said to have a prime twin made up of the same digits.

Examples

			170 -> 017 (forbidden), 071 (forbidden), 107 (prime), 170 (even), 701 (prime), 710 (even) -> conclusion: Two prime numbers.
		

Links

• Andreas Boe, Table of n, a(n) for n = 1..14440

Crossrefs

A245808: Monoprimatic permutable numbers

A246044: Monoprimatic permutable primes

A246045: Biprimatic permutable primes

Programs

Mathematica

Select[Range[500],Count[FromDigits/@Select[Permutations[IntegerDigits[#]], #[[1]] != 0&],?PrimeQ]==2&] (* _Harvey P. Dale, Oct 23 2018 *)