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A066877
a(n) = omega(n!-1), where omega is the number of distinct primes dividing n, A001221.
2
0, 0, 1, 1, 2, 1, 1, 2, 2, 2, 4, 1, 2, 1, 4, 2, 3, 3, 3, 2, 4, 3, 2, 2, 3, 2, 2, 4, 5, 1, 3, 1, 1, 2, 3, 2, 5, 1, 4, 2, 4, 4, 7, 4, 5, 5, 2, 4, 3, 2, 5, 5, 4, 6, 6, 5, 6, 5, 2, 3, 4, 4, 5, 4, 6, 4, 7, 2, 6, 5, 5, 3, 4, 5, 7, 3, 5, 4, 2, 4, 4, 4, 4, 6, 2, 3, 4
OFFSET
1,5
MATHEMATICA
Table[ Length[ FactorInteger[ n! - 1]], {n, 1, 30}]
CROSSREFS
Sequence in context: A117592 A117942 A290092 * A240071 A029255 A029272
KEYWORD
hard,nonn
AUTHOR
Robert G. Wilson v, Jan 21 2002
EXTENSIONS
a(52) corrected and more terms added by Amiram Eldar, Oct 03 2019
STATUS
approved