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A056839
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Squarefree part of lcm(1,...,n).
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1
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1, 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, 40112098026, 40112098026
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OFFSET
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0,3
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LINKS
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FORMULA
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EXAMPLE
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n=65: lcm(1..65) = 1182266884102822267511361600, floor(sqrt(65))=8, lcm(1..8) = 8*3*5*7 = 840; a(65) = lcm(1..65)/lcm(1..8)^2 = 1675548305134385299761 is squarefree.
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MAPLE
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b:= proc(n) b(n):= `if`(n=0, 1, ilcm(b(n-1), n)) end:
a:= n-> mul(i[1]^irem(i[2], 2), i=ifactors(b(n))[2]):
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MATHEMATICA
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PROG
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(PARI) a(n) = core(lcm(vector(n, k, k))); \\ Michel Marcus, Oct 27 2017
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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