HP-35 origin

[brickviking]

(06-19-2018 10:22 AM)StephenG1CMZ Wrote:  

(06-18-2018 12:02 AM)brickviking Wrote:  If I took that phrase literally (Pi !!!), HP-50G calculates that to be 9.99999999999 E499. Somehow, I think even HP wouldn't be that crazy. Pi !! came to about 7380.55555766, and Pi! comes to 7.1881-ish, or so my HP-34C told me back in the day. That might be closer to the scale that HP was originally thinking of.

(Post 244)

I am curious - How did you parse that expression?

X!! Is not the same as (X!)! If you have heard of double-factorials, although of course it is if you haven't, ! Being an ambiguous mathematical symbol.

Is that x!!! (A triple factorial?)
(X!!)! (Factorial of a double factorial)
(X!)!! (Double factorial of a factorial)
((X!)!)! (Factorial of a factorial of a factorial)

I parsed that as the following procedure would indicate:
\((((\pi!)!)!)\), therefore would have approximately been:
\(\pi! = 7.18808272898\)
\(7.18808272898! = 7380.55555766 \)
\(7380.55555766! = OVERFLOW \)(at least for my 50G)

And I'd have to check what on earth are double-factorials or triple-factorials. I haven't heard of such a beast.

(Later) Oh, so that's what those are. Interesting.

(Post 246)