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%I #17 Feb 13 2020 20:14:48
%S 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
%N a(n) = number of distinct prime divisors of (9+prime(n)!)/9.
%C Conjecture: all prime divisors in A139089 are distinct
%C a(31) >= 4. - _Amiram Eldar_, Feb 13 2020
%H FactorDB, <a href="http://factordb.com/index.php?query=%289%2B127%21%29%2F9">Status of a(31) = (9+127!)/9</a>.
%F a(n) = A001221(A139089(n)). - _Amiram Eldar_, Feb 13 2020
%t a = {}; Do[w = (Prime[n]! + 9)/9; AppendTo[a, w], {n, 4, 16}]; a
%t PrimeNu[(9+Prime[Range[4,25]]!)/9] (* _Harvey P. Dale_, Jul 25 2019 *)
%Y Cf. A082672, A089085, A089130, A117141, A007749, A139056-A139066, A020458, A139068, A137390, A139070-A139075, A136019, A136020, A136026, A136027, A139089-A139092.
%K nonn,more
%O 4,1
%A _Artur Jasinski_, Apr 08 2008
%E More terms from _Jon E. Schoenfield_, Jul 16 2010
%E a(23)-a(30) using factordb.com from _Amiram Eldar_, Feb 13 2020
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