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This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A177876 a(n) is the number of distinct prime factors in Lucas-Lehmer numbers A003010(k-2)/(2^k-1), where k = A000043(n+1).

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%I A177876 #23 Jul 30 2024 05:07:23
%S A177876 2,3,3,4
%N A177876 a(n) is the number of distinct prime factors in Lucas-Lehmer numbers A003010(k-2)/(2^k-1), where k = A000043(n+1).
%C A177876 a(5) of this sequence will require the factorization of A003010(15), an 18742-digit integer divisible by 2^17-1.
%e A177876 a(1)=2 because A003010(1)=14, contains exactly 2 distinct prime factors;
%e A177876 a(2)=3 because A003010(3)=37634, contains exactly 3 distinct prime factors;
%e A177876 a(3)=3 because A003010(5)=2005956546822746114, contains exactly 3 distinct prime factors;
%e A177876 a(4)=4 because A003010(11)=the associated 1172-digit Lucas-Lehmer number, contains exactly 4 distinct prime factors.
%Y A177876 Cf. A000040, A000668, A003010, A177874, A177875, A177879, A177892
%K A177876 nonn,hard,bref,more
%O A177876 1,1
%A A177876 _G. L. Honaker, Jr._, Dec 13 2010
%E A177876 Definition corrected by _Max Alekseyev_, Jul 29 2024