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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
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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; refs; listen; history; internal format)
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OFFSET
| 1,1
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COMMENTS
| 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
| 20706 = 2.3.7.17.29 and 2+3+7+17 = 29 hence 20706 is in the sequence
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PROG
| (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
| Cf. A071141.
Sequence in context: A164596 A131647 A071141 * A071142 A179321 A039517
Adjacent sequences: A071309 A071310 A071311 * A071313 A071314 A071315
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KEYWORD
| easy,nonn
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AUTHOR
| Benoit Cloitre (benoit7848c(AT)orange.fr), Jun 11 2002
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