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%I #19 Feb 23 2014 02:04:51
%S 1,3,2,4,2,5,3,5,3,5,2,5,3,6,3,7,2,6,3,5,3,6,3,6,5,5,4,6,2,8,3,7,4,6,
%T 3,6,3,6,3,7,2,6,4,5,4,7,3,8,4,6,3,7,3,8,4,6,3,6,2,6,4,8,5,9,3,6,3,6,
%U 3,8,2,7,4,5,5,6,3,8,5,7,5,6,3,6,4,6
%N Number of prime divisors (with multiplicity) of n^2 - 1.
%H T. D. Noe, <a href="/A193295/b193295.txt">Table of n, a(n) for n = 2..10000</a>
%t Table[PrimeOmega[n^2 - 1], {n, 100}] (* _Vladimir Joseph Stephan Orlovsky_, Jul 22 2011 *)
%o (PARI) a(n)=bigomega(n^2-1) \\ _Charles R Greathouse IV_, Jul 30 2011
%Y Cf. A046051, A054992, A054990, A054991, A082863.
%K nonn
%O 2,2
%A _Vladimir Joseph Stephan Orlovsky_, Jul 22 2011