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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. 0
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 (list; graph; refs; listen; history; internal format)
OFFSET

1,1

COMMENTS

Leading zeros in the permutations are ignored.

LINKS

C. Hilliard, Comments and PARI program.

Wikipedia, Permutation

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.

PROG

(PARI) Cf. C. 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) ]; [From Klaus Brockhaus, Jun 14 2009]

CROSSREFS

Sequence in context: A033258 A095647 A039555 * A168475 A142662 A178416

Adjacent sequences:  A161400 A161401 A161402 * A161404 A161405 A161406

KEYWORD

base,nonn

AUTHOR

Cino Hilliard (hillcino368(AT)hotmail.com), Jun 09 2009

EXTENSIONS

Edited by Klaus Brockhaus (klaus-brockhaus(AT)t-online.de), Jun 14 2009

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Last modified February 15 23:53 EST 2012. Contains 205860 sequences.