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%I #32 Feb 25 2023 17:04:10
%S 1,3,2,5,3,6,4,7,3,7,4,10,4,8,6,10,5,9,4,13,7,9,4,14,7,8,6,14,6,13,3,
%T 13,8,11,11,15,6,9,9,17,5,14,5,15,10,9,6,19,7,14,8,18,8,16,10,19,7,11,
%U 6,24,5,8,10,16,8,17,6,20,9,22,7,21,7,13,14,17,10,16,8,23,10,12,5,24
%N Number of prime factors of 8^n - 1 (counted with multiplicity).
%H Max Alekseyev, <a href="/A057953/b057953.txt">Table of n, a(n) for n = 1..500</a> (first 402 terms from Amiram Eldar)
%H S. S. Wagstaff, Jr., <a href="https://homes.cerias.purdue.edu/~ssw/cun/index.html">The Cunningham Project</a>
%F Mobius transform of A085033. - _T. D. Noe_, Jun 19 2003
%F a(n) = A001222(A024088(n)) = A046051(3*n). - _Amiram Eldar_, Feb 02 2020
%t PrimeOmega/@(8^Range[90]-1) (* _Harvey P. Dale_, May 24 2018 *)
%o (Magma) f:=func<n|&+[p[2]: p in Factorization(n)]>; [f(8^n - 1):n in [1..90]]; // _Marius A. Burtea_, Feb 02 2020
%Y bigomega(b^n-1): A057951 (b=10), A057952 (b=9), this sequence (b=8), A057954 (b=7), A057955 (b=6), A057956 (b=5), A057957 (b=4), A057958 (b=3), A046051 (b=2).
%Y Cf. A001222, A024088, A085033, A274908.
%K nonn
%O 1,2
%A _Patrick De Geest_, Nov 15 2000
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