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A161404 Numbers n such that the count of primes among the permutations of the digits of n is greater than 7. 0
1013, 1031, 1039, 1049, 1079, 1093, 1094, 1097, 1103, 1123, 1130, 1132, 1139, 1193, 1213, 1231, 1237, 1273, 1279, 1297, 1301, 1309, 1310, 1312, 1319, 1321, 1327, 1349, 1367, 1372, 1376, 1390, 1391, 1394, 1409, 1439, 1457, 1475, 1478, 1487, 1490, 1493 (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

1013 has eight permutations of its digits 1, 0, 1, 3 that form a prime, namely 113, 131, 311, 1013, 1031, 1103, 1301, 3011. So the count of primes for 1013 is greater than 7 and 1013 is in the sequence.

PROG

(PARI) Cf. C. Hilliard link.

(MAGMA) [ n: n in [1..1500] | #[ s: s in Seqset([ Seqint([m(p[i]):i in [1..#x] ], 10): p in Permutations(Seqset(x)) ]) | IsPrime(s) ] gt 7 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: A165295 A069489 A157008 * A126239 A120214 A096928

Adjacent sequences:  A161401 A161402 A161403 * A161405 A161406 A161407

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 12:25 EST 2012. Contains 205786 sequences.