A161401 Numbers n such that the count of primes among the permutations of the digits of n is greater than 1.

13, 17, 31, 37, 71, 73, 79, 97, 101, 103, 104, 106, 107, 109, 110, 113, 118, 119, 124, 125, 127, 128, 130, 131, 133, 136, 137, 139, 140, 142, 146, 149, 152, 157, 160, 163, 164, 167, 169, 170, 172, 173, 175, 176, 179, 181, 182, 190, 191, 193, 194, 196, 197

Offset

1,1

Comments

Leading zeros in the permutations are ignored.

Links

Vincenzo Librandi, Table of n, a(n) for n = 1..4690

Cino Hilliard, Comments and PARI program.

Wikipedia, Permutation

Example

13 has two permutations of its digits 1, 3 that form a prime, namely 13, 31. So the count of primes for 13 is greater than 1 and 13 is in the sequence.

Mathematica

Select[Range[300], Count[FromDigits/@Permutations[IntegerDigits[#]], _?PrimeQ]>1&] (* Vincenzo Librandi, Feb 02 2018 *)

Prog

(PARI) See Hilliard link.
(Magma) [ n: n in [1..200] | #[ s: s in Seqset([ Seqint([m(p[i]):i in [1..#x] ], 10): p in Permutations(Seqset(x)) ]) | IsPrime(s) ] gt 1 where m is map< x->y | [<x[i], y[i]>:i in [1..#x] ] > where x is [1..#y] where y is Intseq(n, 10) ]; // Klaus Brockhaus, Jun 14 2009

Crossrefs

Cf. A161402, A161403, A161404.

Sequence in context: A107159 A138375 A180526 * A225035 A344626 A006567

Adjacent sequences: A161398 A161399 A161400 * A161402 A161403 A161404

Keyword

base,nonn

Author

Cino Hilliard, Jun 09 2009

Extensions

Edited by Klaus Brockhaus, Jun 14 2009

Status

approved