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Search: id:A056839
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| A056839 |
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Square-free part of LCM[1,...,n]. |
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3
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| 1, 2, 6, 3, 15, 15, 105, 210, 70, 70, 770, 770, 10010, 10010, 10010, 5005, 85085, 85085, 1616615, 1616615, 1616615, 1616615, 37182145, 37182145, 7436429, 7436429, 22309287, 22309287, 646969323, 646969323, 20056049013, 40112098026
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OFFSET
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0,2
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FORMULA
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a(n)=A007913(A003418(n))=LCM[n]/LCM[q]^2, where LCM[n]=LCM[1, ..., n]=A003418(n), q=Floor[Sqrt[n]]=A000196(n)
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EXAMPLE
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n=65, LCM[1,..,65]=1182266884102822267511361600, Floor(Sqrt(65))=8, LCM[8]=8.3.5.7]=840, a(65)=LCM(65)/LCM(8)^2=1675548305134385299761 is square-free.
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CROSSREFS
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A007913, A003418, A000196.
Sequence in context: A072155 A094299 A121566 this_sequence A071301 A145642 A056195
Adjacent sequences: A056836 A056837 A056838 this_sequence A056840 A056841 A056842
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KEYWORD
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nonn
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AUTHOR
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Labos E. (labos(AT)ana.sote.hu), Aug 29 2000
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