

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
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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 * A252634 A250610 A126239
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



