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%I #22 Sep 30 2021 15:24:14
%S 1,1,1,1,1,1,2,2,2,1,1,1,2,1,3,2,2,2,2,2,5,3,4,3,1,3,5,7,2,2,6,4,4,5,
%T 4,3,3,3,4,4,4,2,5,5,7,2,3,8,9,3,3,4,3,2,4,2,8,6,4,3,8,2,5,4,5,1,5,5,
%U 4,5,4
%N Number of prime factors of 1+(n!)^2 (with multiplicity).
%H H. Ibstedt, <a href="https://www.gallup.unm.edu/~smarandache/SN/SIntegerSeq.pdf">A Few Smarandache Integer Sequences</a>, Smarandache Notions Journal, Vol. 8, No. 1-2-3, 1997, pp. 171-183.
%F a(n) = A001222(A020549(n)). - _Michel Marcus_, Aug 09 2021
%t Table[Length[FactorInteger[1 + (n!)^2]], {n, 0, 20}] (* _T. D. Noe_, Oct 17 2011 *)
%o (PARI) a(n)=bigomega(n!^2+1) \\ _Charles R Greathouse IV_, Sep 20 2012
%Y Cf. A001222, A020549.
%K nonn,more
%O 0,7
%A Charles T. Le (charlestle(AT)yahoo.com)
%E Corrected by _Arkadiusz Wesolowski_, Oct 17 2011
%E Corrected by _Charles R Greathouse IV_, Sep 20 2012
%E a(38)-a(54) from _Giovanni Resta_, Jun 26 2018
%E a(55)-a(61) from _Jinyuan Wang_, Aug 09 2021
%E a(62)-a(70) from _Sean A. Irvine_, Sep 30 2021
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