[ 3 / biz / cgl / ck / diy / fa / ic / jp / lit / sci / vr / vt ] [ index / top / reports ] [ become a patron ] [ status ]
2023-11: Warosu is now out of extended maintenance.

/sci/ - Science & Math

View post   
File: 10 KB, 251x205, fuck..jpg [View same] [iqdb] [saucenao] [google]
4309497 No.4309497 [Reply] [Original]

i'm not sure how to phrase this properly, but what is the opposite of factorial. i'm doing a cs worksheet on algorithms and it asks for us to give the max n given f(n) (in this case it's n!) and t…i want to start with this:

n!=t

and turn it into:

n=_____

what do?

>> No.4309502
File: 203 KB, 640x360, tumblr_lj02g7Ibfa1qibpzbo1_1280.png [View same] [iqdb] [saucenao] [google]
4309502

If <span class="math">n! = t[/spoiler] then <span class="math">n = \frac{t}{!}[/spoiler]

>> No.4309510

n = t/(n-1)!

cannot determine

>> No.4309518
File: 182 KB, 569x571, Angry Gorilla..jpg [View same] [iqdb] [saucenao] [google]
4309518

>>4309510
so it's undo-able then?

>> No.4309525

>>4309518
>>4309510
Well n! is injective so you'd suppose an inverse exists.

>> No.4309528

Recursive function, undoable:

http://www.wolframalpha.com/input/?i=solve+gamma%28x%2B1%29%3Dy+for+x

>> No.4309530
File: 250 KB, 680x353, itn-that-cute.png [View same] [iqdb] [saucenao] [google]
4309530

>>4309528
Fails horizontal line test, not invertible.

>> No.4309531

>>4309502

But a factorial sign not prefaced by a number of variable is entirely meaningless

>> No.4309620

Look up invgamma, OP. Knowing that <span class="math">n!= \Gamma(n+1) [/spoiler], you should find what you need.

>> No.4309625

>>4309531
i think he was joking

if not he was stupid enough to make me laugh