A211654 Primes that remain prime when their digits are sorted into nondecreasing order.

2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 47, 59, 67, 71, 73, 79, 89, 97, 101, 103, 107, 109, 113, 127, 131, 137, 139, 149, 157, 167, 173, 179, 193, 197, 199, 223, 227, 229, 233, 239, 257, 269, 271, 277, 293, 307, 311, 317, 337, 347, 349, 359, 367, 373

Offset

1,1

Comments

In sequence A004185 these are referred to as "sortable primes". Nontrivial terms (with digits not in nondecreasing order) are listed in A086042. - M. F. Hasler, Jul 30 2019.

Links

Francis J. McDonnell, Table of n, a(n) for n = 1..10000

Francis J. McDonnell, Java Program

Example

173 is prime and after the digits are sorted into nondecreasing order we obtain 137, which is prime.

Mathematica

Select[Prime[Range[200]], PrimeQ[FromDigits[Sort[IntegerDigits[#]]]] &] (* T. D. Noe, Apr 17 2012 *)

Prog

(PARI) select( is_A211654(p)={isprime(fromdigits(vecsort(digits(p))))&&isprime(p)}, primes([1, 999])) \\ M. F. Hasler, Jul 30 2019
(Magma) [p:p in PrimesUpTo(400)| IsPrime(Seqint(Reverse(Sort(Intseq(p, 10)))))]; // Marius A. Burtea, Jul 30 2019

Crossrefs

Cf. A028864, A028867, A211655.

Cf. A086042 (nontrivial solutions), A004185 (n with digits sorted).

Sequence in context: A256484 A238242 A197298 * A363998 A038612 A012883

Adjacent sequences: A211651 A211652 A211653 * A211655 A211656 A211657

Keyword

nonn,base

Author

Francis J. McDonnell, Apr 17 2012

Status

approved