OFFSET
1,2
COMMENTS
Factorial splitting: write n! = x*y with x <= y and x maximal; sequence gives value of y. Inequality "x < y" gives the same sequence, except that a(1) is not defined.
The integer part of square root of n! (A055226(n)) is situated between x and y.
LINKS
Max Alekseyev, Table of n, a(n) for n = 1..140
FORMULA
EXAMPLE
Divisors of 6!=720 are {1, 2, 3, 4, 5, 6, ..., 24, 30, ..., 360, 720}. a(6)=30, the 16th one from the 30 divisors of 720.
MATHEMATICA
Table[ Part[ Divisors[ w! ], 1+Floor[ DivisorSigma[ 0, n! ]/2 ] ], {w, a, b} ]
CROSSREFS
KEYWORD
nonn
AUTHOR
Labos Elemer, Apr 26 2001
EXTENSIONS
More terms from Don Reble, Dec 13 2001
STATUS
approved