Rational Binomial Coefficients

[Thomas Klemm]

(01-03-2019 05:52 AM)Eddie W. Shore Wrote:  There are algorithms, but the program RATBIN uses the definition.

With the HP-15C we can use:

\(\binom{p}{n}=\frac{p!}{n!(p-n)!}\)

Code:

001-    42 0    x!
002-      34    x<>y
003-   43 36    LSTx
004-      34    x<>y
005-    42 0    x!
006-      34    x<>y
007-   43 36    LSTx
008-      30    -
009-    42 0    x!
010-      20    ×
011-      10    ÷

Examples:

2 ENTER 0.5 R/S
-0.1250

3 ENTER 0.5 R/S
0.0625

4 ENTER 0.5 R/S
-0.0391

5 ENTER 0.5 R/S
0.0273

Cheers
Thomas