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A161402
Numbers having more than 2 primes among the permutations of their digits.
3
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.
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
KEYWORD
base,nonn
AUTHOR
Cino Hilliard, Jun 09 2009
EXTENSIONS
Edited by Klaus Brockhaus, Jun 14 2009
STATUS
approved