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A099946
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a(n) = lcm{1, 2, ..., n}/(n*(n-1)), n >= 2.
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4
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1, 1, 1, 3, 2, 10, 15, 35, 28, 252, 210, 2310, 1980, 1716, 3003, 45045, 40040, 680680, 612612, 554268, 503880, 10581480, 9699690, 44618574, 41186376, 114406600, 106234700, 2868336900, 2677114440, 77636318760, 145568097675, 136745788725
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OFFSET
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2,4
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LINKS
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FORMULA
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MAPLE
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a:= n-> ilcm(seq(k, k=1..n))/n/(n-1): seq(a(n), n=2..37); # Emeric Deutsch, Jun 13 2005
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MATHEMATICA
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Table[LCM@@Range[n]/(n(n-1)), {n, 2, 40}] (* Harvey P. Dale, Jan 14 2011 *)
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PROG
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(Python)
from math import gcd
def lcm(a, b):
return (a * b) // gcd(a, b)
def f(lim):
l = 1
for n in range(2, lim + 1):
l = lcm(n, l)
print(n, l // (n * (n - 1)))
(PARI) a(n) = lcm(vector(n, i, i))/(n*(n-1)); \\ Michel Marcus, Jul 25 2014
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CROSSREFS
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KEYWORD
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nonn,easy
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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