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A161401 Numbers n such that the count of primes among the permutations of the digits of n is greater than 1. 4
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 (list; graph; refs; listen; history; text; internal format)
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

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Last modified July 28 11:11 EDT 2021. Contains 346326 sequences. (Running on oeis4.)