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A083720
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Product of the primes less than the greatest prime factor of n but not dividing n.
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7
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1, 1, 2, 1, 6, 1, 30, 1, 2, 3, 210, 1, 2310, 15, 2, 1, 30030, 1, 510510, 3, 10, 105, 9699690, 1, 6, 1155, 2, 15, 223092870, 1, 6469693230, 1, 70, 15015, 6, 1, 200560490130, 255255, 770, 3, 7420738134810, 5, 304250263527210, 105, 2, 4849845
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OFFSET
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1,3
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COMMENTS
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a(n) is squarefree, and all squarefree numbers appear infinitely often. a(m) = a(n) if and only if rad(m) = rad(n), where rad is A007947. - Charles R Greathouse IV, Apr 09 2024
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LINKS
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FORMULA
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MATHEMATICA
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Array[Times @@ Complement[Prime@ Range@ PrimePi@ Last[#], #] &[FactorInteger[#][[All, 1]]] &, 46] (* Michael De Vlieger, Apr 09 2024 *)
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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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