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Search: id:A161401
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%I A161401
%S A161401 13,17,31,37,71,73,79,97,101,103,104,106,107,109,110,113,118,119,124,
%T A161401 125,127,128,130,131,133,136,137,139,140,142,146,149,152,157,160,163,
%U A161401 164,167,169,170,172,173,175,176,179,181,182,190,191,193,194,196,197
%N A161401 Numbers n such that the count of primes among the permutations of the 
               digits of n is greater than 1.
%C A161401 Leading zeros in the permutations are ignored.
%H A161401 Wikipedia,<a href="http://en.wikipedia.org/wiki/Permutation">Permutation</
               a>
%H A161401 C. Hilliard, <a href="a161401.txt">Comments and PARI program.</a>
%e A161401 13 has two permutations of its digits 1, 3 that form a prime, namely 
               13, 31. So the count of primes for 13 is greater than 1 and 13 is 
               in the sequence.
%o A161401 (PARI) Cf. C. Hilliard link.
%o A161401 (MAGMA) [ n: n in [1..200] | #[ s: s in Seqset([ Seqint([m(p[i]):i in 
               [1..#x] ], 10): p in Permutations(Seqset(x)) ]) | IsPrime(s) ] gt 
               1 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]
%Y A161401 Sequence in context: A033210 A107159 A138375 this_sequence A006567 A108388 
               A083983
%Y A161401 Adjacent sequences: A161398 A161399 A161400 this_sequence A161402 A161403 
               A161404
%K A161401 base,nonn
%O A161401 1,1
%A A161401 Cino Hilliard (hillcino368(AT)hotmail.com), Jun 09 2009
%E A161401 Edited by Klaus Brockhaus (klaus-brockhaus(AT)t-online.de), Jun 14 2009

    
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Last modified December 13 23:45 EST 2009. Contains 170824 sequences.


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