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Number of prime factors of 11^n + 1 (counted with multiplicity).
7

%I #7 Jan 04 2024 17:01:41

%S 1,3,2,5,2,4,4,4,3,7,3,7,4,6,5,8,3,6,5,7,4,7,4,7,7,6,3,10,6,6,6,7,4,

%T 13,6,11,7,5,4,11,5,6,9,5,6,13,6,7,5,8,6,11,3,7,9,13,7,12,6,7,8,6,4,

%U 13,3,10,8,9,7,14,8,6,10,8,8,13,6,12,12,7,10

%N Number of prime factors of 11^n + 1 (counted with multiplicity).

%H Max Alekseyev, <a href="/A366687/b366687.txt">Table of n, a(n) for n = 0..325</a>

%F a(n) = bigomega(11^n+1) = A001222(A034524(n)).

%t PrimeOmega[11^Range[70]+1]

%o (PARI) a(n)=bigomega(11^n+1)

%Y Cf. A034524, A001222, A057934, A062308, A366686, A366688, A366689, A366690.

%Y Cf. A054992, A057941, A057940, A057939, A057938, A057937, A057936, A057935, A057934, A366713.

%K nonn

%O 0,2

%A _Sean A. Irvine_, Oct 16 2023