(12C) Stirling's approximation

[Gamo]

N! approximation using Forsyth's formula with shorter program steps.

Code:


STO 1
ENTER
X
RCL 1
+
6
1/x
+
√x
1
e^x
/
RCL 1
0.5
+
Y^X
2.5066283
x

Example: input N [R/S]

2.34! ------> 2.34 [R/S] result 2.7971......
4.32! ------> 4.32 [R/S] result 39.2928....
5.43! ------> 5.43 [R/S] result 254.0266...

Gamo