A161402 Numbers having more than 2 primes among the permutations of their digits.

103, 107, 113, 130, 131, 136, 137, 149, 157, 163, 167, 170, 173, 175, 176, 179, 194, 197, 199, 301, 307, 310, 311, 316, 317, 337, 359, 361, 370, 371, 373, 379, 389, 395, 397, 398, 419, 491, 517, 539, 571, 593, 613, 617, 631, 671, 701, 703, 709, 710, 713

Offset

1,1

Comments

Leading zeros in the permutations are ignored.

Links

Table of n, a(n) for n=1..51.

C. Hilliard, Comments and PARI program.

Wikipedia,Permutation

Example

103 has three permutations of its digits 1, 0, 3 that form a prime, namely 103, 031, 013. So the count of primes for 103 is greater than 2 and 103 is in the sequence.

Mathematica

Select[Range[800], Count[FromDigits/@Permutations[ IntegerDigits[#]], _?PrimeQ]> 2&] (* Harvey P. Dale, Nov 24 2010 *)

Prog

(PARI) See Hilliard link.
(Magma) [ n: n in [1..720] | #[ s: s in Seqset([ Seqint([m(p[i]):i in [1..#x] ], 10): p in Permutations(Seqset(x)) ]) | IsPrime(s) ] gt 2 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

Sequence in context: A235155 A167841 A213311 * A318295 A165294 A046076

Adjacent sequences: A161399 A161400 A161401 * A161403 A161404 A161405

Keyword

base,nonn

Author

Cino Hilliard, Jun 09 2009

Extensions

Edited by Klaus Brockhaus, Jun 14 2009

Status

approved