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A139092
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a(n) = number of distinct prime divisors of (9+prime(n)!)/9.
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4
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3, 3, 2, 2, 2, 3, 2, 3, 4, 4, 5, 3, 3, 6, 5, 2, 3, 4, 3, 3, 4, 4, 4, 3, 7, 3, 3
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OFFSET
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4,1
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COMMENTS
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Conjecture: all prime divisors in A139089 are distinct
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LINKS
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FORMULA
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MATHEMATICA
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a = {}; Do[w = (Prime[n]! + 9)/9; AppendTo[a, w], {n, 4, 16}]; a
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CROSSREFS
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Cf. A082672, A089085, A089130, A117141, A007749, A139056-A139066, A020458, A139068, A137390, A139070-A139075, A136019, A136020, A136026, A136027, A139089-A139092.
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KEYWORD
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nonn,more
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AUTHOR
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EXTENSIONS
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a(23)-a(30) using factordb.com from Amiram Eldar, Feb 13 2020
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STATUS
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approved
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