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A038610
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Least common multiple of integers less than and prime to n.
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14
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1, 1, 2, 3, 12, 5, 60, 105, 280, 63, 2520, 385, 27720, 6435, 8008, 45045, 720720, 85085, 12252240, 2909907, 3695120, 1322685, 232792560, 37182145, 1070845776, 128707425, 2974571600, 717084225, 80313433200, 215656441, 2329089562800
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OFFSET
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1,3
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COMMENTS
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LINKS
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FORMULA
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a(n) = e^[Sum_{k=1..n} (1-floor(n^k/k)+floor((n^k -1)/k))*Mangoldt(k)] where Mangoldt is the Mangoldt function. - Anthony Browne, Jun 16 2016
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EXAMPLE
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Since 1, 5, 7, and 11 are relatively prime to 12, a(12) = LCM(1,5,7,11) = 385.
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MAPLE
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MATHEMATICA
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Table[ LCM@@ Flatten[ Position[ GCD[ n, # ]& /@ Range[ n ], 1 ] ], {n, 32} ]
Join[{1}, Table[LCM@@Select[Range[n-1], CoprimeQ[#, n]&], {n, 2, 40}]] (* Harvey P. Dale, Mar 05 2016 *)
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PROG
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(Haskell)
a038610 = foldl lcm 1 . a038566_row
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CROSSREFS
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KEYWORD
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nonn,nice
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AUTHOR
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STATUS
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approved
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