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 A139092 a(n) = number of distinct prime divisors of (9+prime(n)!)/9. 4
 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 (list; graph; refs; listen; history; text; internal format)
 OFFSET 4,1 COMMENTS Conjecture: all prime divisors in A139089 are distinct a(31) >= 4. - Amiram Eldar, Feb 13 2020 LINKS FactorDB, Status of a(31) = (9+127!)/9. FORMULA a(n) = A001221(A139089(n)). - Amiram Eldar, Feb 13 2020 MATHEMATICA a = {}; Do[w = (Prime[n]! + 9)/9; AppendTo[a, w], {n, 4, 16}]; a PrimeNu[(9+Prime[Range[4, 25]]!)/9] (* Harvey P. Dale, Jul 25 2019 *) CROSSREFS Cf. A082672, A089085, A089130, A117141, A007749, A139056-A139066, A020458, A139068, A137390, A139070-A139075, A136019, A136020, A136026, A136027, A139089-A139092. Sequence in context: A133884 A065775 A096837 * A021305 A075788 A324080 Adjacent sequences:  A139089 A139090 A139091 * A139093 A139094 A139095 KEYWORD nonn,more AUTHOR Artur Jasinski, Apr 08 2008 EXTENSIONS More terms from Jon E. Schoenfield, Jul 16 2010 a(23)-a(30) using factordb.com from Amiram Eldar, Feb 13 2020 STATUS approved

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Last modified June 5 12:47 EDT 2020. Contains 334840 sequences. (Running on oeis4.)