OFFSET
0,4
COMMENTS
For n > 4, there is always the factorization n! = (2*n) * (n!/(2*n)), so a(n) is only 0 for n = 1 or 2. - Franklin T. Adams-Watters, Jul 28 2011.
It appears that this sequence is O(n). - Franklin T. Adams-Watters, Jul 28 2011.
LINKS
William Rex Marshall, Pascal program
EXAMPLE
For n=5, n! = 120. Any factorization of 120 into 3 (or more) factors will have a factor <= 5, so we take the most central factorization into two factors, 120 = 10*12, the maximum of {10, 12} is 12, thus a(5) = 12.
CROSSREFS
KEYWORD
nonn
AUTHOR
William Rex Marshall, Jul 28 2011
STATUS
approved