They are an important aspect of experimental design when you have two (or more) explanatory factors are different levels and the effect of the factors may be different from simply the sum of the effects of each factor separately - because of interaction between factors.
Factorial designs
Robert A. McLean has written: 'Applied factorial and fractional designs' -- subject(s): Factorial experiment designs 'Financial management in health care organizations' -- subject(s): Medical care, Health services administration, Finance, Medical economics
K. G. Janardan has written: 'Recovery of coliforms by the MPN and MF techniques using a 2n - factorial experimental design' -- subject(s): Enterobacteriaceae, Factorial experiment designs, Identification, Sanitary microbiology, Technique
The value of 9 factorial plus 6 factorial is 363,600
It is 4060.
factorial of -1
26 factorial is 403,291,461,126,605,635,584,000,000
18 factorial is 6,402,373,705,728,000.
Zero factorial = 1
34 factorial = 295,232,799,039,604,140,847,618,609,643,520,000,000.
1 factorial = 1
27 factorial = 10,888,869,450,418,352,160,768,000,000