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%I #46 Jul 09 2023 11:20:44
%S 1,2,2,3,2,3,6,3,5,5
%N The number of distinct prime factors in Lucas-Lehmer number A003010(n).
%C a(10)>2: results from www.factordb.com. - _R. J. Mathar_, Dec 15 2010
%C a(11)=4, factorization added to www.factordb.com. - _Sean A. Irvine_, Mar 25 2011
%H Dario Alejandro Alpern, <a href="https://www.alpertron.com.ar/ECM.HTM">Factorization using the Elliptic Curve Method (along with sigma_0, sigma_1 and phi functions)</a>
%F a(n) = A001221(A003010(n)).
%t Table[PrimeNu[Ceiling[(2 + Sqrt[3])^(2^n)]], {n,0,5}] (* _G. C. Greubel_, May 16 2017 *)
%o (PARI) a=4; until(a=a^2-2, print1(omega(a)", ")) \\ _M. F. Hasler_, Dec 14 2010
%Y Cf. A001221, A003010, A177876.
%K nonn,hard,more
%O 0,2
%A _G. L. Honaker, Jr._, Dec 14 2010
%E a(9) from _Wang Runsen_, Oct 26 2020
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