Probability Functions; Factorial; Gamma; Probability - HP 35s User Manual

Probability Functions

Factorial

To calculate the factorial of a displayed non-negative integer x (0 x 253), press
 * 
(the right–shifted key).

Gamma

To calculate the gamma function of a noninteger x, (x), key in (x – 1) and press
 *
. The x! function calculates (x + 1). The value for x cannot be a negative

integer.

Probability

Combinations
To calculate the number of possible sets of n items taken r at a time, enter n first,
 x
, then r (nonnegative integers only). No item occurs more than once in a
set, and different orders of the same r items are not counted separately.
Permutations
To calculate the number of possible arrangements of n items taken r at a time, enter
{
n first, , then r (nonnegative integers only). No item occurs more than
once in an arrangement, and different orders of the same r items are counted
separately.
Seed
To store the number in x as a new seed for the random number generator, press
 
.
Random number generator
 
To generate a random number in the range 0 < x < 1, press . (The
number is part of a uniformly–distributed pseudo–random number sequence. It
passes the spectral test of D. Knuth, The Art of Computer Programming, vol. 2,
Seminumerical Algorithms, London: Addison Wesley, 1981.)
4-15
Real–Number Functions