HP-35 origin

[Gerson W. Barbosa]

(06-18-2018 11:05 PM)brickviking Wrote:  Pretty much: \( n! = Γ(n+1) \), if I remember rightly, and I'm sorry if I can't get that Gamma to come out correctly. I had fun trying to generate the inverse... of course that's not defined anywhere mathematically, so I was told.

Do you mean something like that?

I prefer Inverse Factorial, however:

120 XEQ InvFact -> 5

PI SQRT 3 * 4 / XEQ InvFact -> 1.5

163 ENTER ENTER + 1/x + ENTER * 5 * 18 / XEQ InvFact XEQ InvFact -> 3.14159265359

(On Free42)

00 { 89-Byte Prgm }
01▸LBL "InvFact"
02 ENTER
03 LN
04 SQRT
05 0.16
06 RCL× ST L
07 X<>Y
08 2.21
09 ×
10 +
11 0.194
12 +
13 2
14 X<Y?
15 X<>Y
16 X<> ST T
17▸LBL 00
18 R↓
19 R↓
20 STO ST Z
21 X<>Y
22 STO ST T
23 GAMMA
24 ÷
25 +/-
26 1
27 +
28 R↑
29 RCL+ ST T
30 1/X
31 RCL ST T
32 LN
33 STO- ST Y
34 X<> ST L
35 R↓
36 +/-
37 ÷
38 STO- ST Z
39 ABS
40 1ᴇ-30
41 X<Y?
42 GTO 00
43 R↑
44 1
45 -
46 END