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A161403
Numbers n such that the count of primes among the permutations of the digits of n is greater than 3.
2
107, 149, 170, 179, 194, 197, 379, 397, 419, 491, 701, 709, 710, 719, 739, 790, 791, 793, 907, 914, 917, 937, 941, 970, 971, 973, 1003, 1007, 1009, 1012, 1013, 1015, 1016, 1018, 1019, 1021, 1024, 1028, 1030, 1031, 1033, 1036, 1037, 1039, 1042, 1049, 1051
OFFSET
1,1
COMMENTS
Leading zeros in the permutations are ignored.
EXAMPLE
107 has four permutations of its digits 1, 0, 7 that form a prime, namely 107, 017, 071, 701. So the count of primes for 107 is greater than 3 and 107 is in the sequence.
MATHEMATICA
Select[Range[1100], Count[FromDigits/@Permutations[IntegerDigits[#]], _?PrimeQ]>3&] (* Harvey P. Dale, Mar 04 2013 *)
PROG
(PARI) See Hilliard link.
(Magma) [ n: n in [1..1060] | #[ s: s in Seqset([ Seqint([m(p[i]):i in [1..#x] ], 10): p in Permutations(Seqset(x)) ]) | IsPrime(s) ] gt 3 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
KEYWORD
base,nonn
AUTHOR
Cino Hilliard, Jun 09 2009
EXTENSIONS
Edited by Klaus Brockhaus, Jun 14 2009
STATUS
approved