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A048858
Number of prime factors of 1+(n!)^2 (with multiplicity).
0
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, 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, 4, 5, 4
OFFSET
0,7
LINKS
H. Ibstedt, A Few Smarandache Integer Sequences, Smarandache Notions Journal, Vol. 8, No. 1-2-3, 1997, pp. 171-183.
FORMULA
a(n) = A001222(A020549(n)). - Michel Marcus, Aug 09 2021
MATHEMATICA
Table[Length[FactorInteger[1 + (n!)^2]], {n, 0, 20}] (* T. D. Noe, Oct 17 2011 *)
PrimeOmega[1+(Range[0, 20]!)^2] (* Harvey P. Dale, Dec 28 2024 *)
PROG
(PARI) a(n)=bigomega(n!^2+1) \\ Charles R Greathouse IV, Sep 20 2012
CROSSREFS
Sequence in context: A327490 A346529 A238408 * A246465 A172497 A211226
KEYWORD
nonn,more
AUTHOR
Charles T. Le (charlestle(AT)yahoo.com)
EXTENSIONS
Corrected by Arkadiusz Wesolowski, Oct 17 2011
Corrected by Charles R Greathouse IV, Sep 20 2012
a(38)-a(54) from Giovanni Resta, Jun 26 2018
a(55)-a(61) from Jinyuan Wang, Aug 09 2021
a(62)-a(70) from Sean A. Irvine, Sep 30 2021
STATUS
approved