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%I #25 Aug 30 2023 09:53:24
%S 3,3,4,2,5,5,5,3,5,6,5,5,5,4,7,3,4,6,5,4,8,6,4,4,6,5,6,6,4,10,6,4,8,6,
%T 11,8,5,4,9,6,7,7,10,5,12,7,4,6,12,11,8,5,7,9,13,8,9,7,7,9,4,6,14,4,9,
%U 12,6,5,8,10,5,9,6,4,11,7,12,10,7,6,10,6,5,12,8,6,8,5,8,14,11,6,9,6,11
%N Number of prime factors of 7^n + 1 (counted with multiplicity).
%H Max Alekseyev, <a href="/A057937/b057937.txt">Table of n, a(n) for n = 1..387</a> (first 372 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 a(n) = A057954(2n) - A057954(n). - _T. D. Noe_, Jun 19 2003
%F a(n) = A001222(A034491(n)). - _Amiram Eldar_, Feb 02 2020
%t PrimeOmega[Table[7^n + 1, {n, 1, 30}]] (* _Amiram Eldar_, Feb 02 2020 *)
%o (Magma) f:=func<n|&+[p[2]: p in Factorization(n)]>; [f(7^n + 1):n in [1..110]]; // _Marius A. Burtea_, Feb 02 2020
%Y bigomega(b^n+1): A057934 (b=10), A057935 (b=9), A057936 (b=8), this sequence (b=7), A057938 (b=6), A057939 (b=5), A057940 (b=4), A057941 (b=3), A054992 (b=2).
%Y Cf. A001222, A034491, A057954, A227575.
%K nonn
%O 1,1
%A _Patrick De Geest_, Oct 15 2000
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