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Search: id:A161925
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| A161925 |
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Numbers n such that largest prime factor of n is also largest prime factor of nth composite number. |
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+0
1
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| 6, 15, 24, 26, 28, 30, 55, 93, 99, 105, 112, 182, 209, 276, 292, 300, 304, 308, 312
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OFFSET
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1,1
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EXAMPLE
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If n=6=2*3 and composite(6)=12=2*2*3, then 3=3 and a(1)=6. If n=15=3*5 and composite(15)=25=5*5, then 5=5 and a(2)=15. If n=24=2*2*2*3 and composite(24)=36=2*2*3*3, then 3=3 and a(3)=24, etc.
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CROSSREFS
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Cf. A000027, A002808.
Sequence in context: A130178 A100410 A095032 this_sequence A043477 A055040 A017233
Adjacent sequences: A161922 A161923 A161924 this_sequence A161926 A161927 A161928
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KEYWORD
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nonn
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AUTHOR
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Juri-Stepan Gerasimov (2stepan(AT)rambler.ru), Jun 22 2009, Jun 27 2009
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