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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; text; internal format)
OFFSET

1,1

COMMENTS

Leading zeros in the permutations are ignored.

LINKS

Table of n, a(n) for n=1..42.

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, Jun 09 2009

EXTENSIONS

Edited by Klaus Brockhaus, Jun 14 2009

STATUS

approved

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Last modified November 26 03:51 EST 2014. Contains 250017 sequences.