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Search: id:A071312
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| A071312 |
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Squarefree numbers such that the largest prime factor = sum of other prime factors. |
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+0
1
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| 30, 70, 286, 646, 1798, 3135, 3526, 3570, 6279, 7198, 8855, 8970, 10366, 10626, 10695, 11571, 16095, 16530, 17255, 17391, 20615, 20706, 20735, 20806, 23326, 24738, 24882, 26691, 28083, 31031, 36519, 36890, 38086, 38130, 41151, 41615
(list; graph; listen)
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OFFSET
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1,1
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COMMENT
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If n = p(1)*p(2)*...p(r) is in the sequence, where p(r) is the largest prime factor, then p(r) = p(1)+p(2)+...+p(r-1)
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EXAMPLE
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20706 = 2.3.7.17.29 and 2+3+7+17 = 29 hence 20706 is in the sequence
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PROGRAM
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(PARI) for(n=2, 100000, if(issquarefree(n)*sum(i=1, omega(n)-1, component(component(factor(n), 1), i))==vecmax(factor(n, 1)), print1(n, ", ")))
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CROSSREFS
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Cf. A071141.
Sequence in context: A164596 A131647 A071141 this_sequence A071142 A039517 A045560
Adjacent sequences: A071309 A071310 A071311 this_sequence A071313 A071314 A071315
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KEYWORD
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easy,nonn
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AUTHOR
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Benoit Cloitre (benoit7848c(AT)orange.fr), Jun 11 2002
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