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#1 Exercises » Solve the equation » 2023-02-16 10:30:10

imcute
Replies: 1

Compute the inverse of xlnx-x.
If you can't,tell my why.(i didnt solve this either,i dont even know if its elementary(no pun intended)although i proved one of it by not getting an answer when asking math teacher)

#2 This is Cool » Derivatives of the busy beaver function » 2023-01-27 14:21:56

imcute
Replies: 0

Define βB(x,y) as BB(x) but restricted to an input size of y.For infinite y,it is uncomputable,otherwise the halting problem would be solvable by simulation.
For finite y,it is computable by brute force.It is monotonic with respect to y(if x>y,βB(n,x)>βB(n,y))

Define Bβ(x) as the smallest y which βB(x,y)=BB(x).It is finite for finite x.(because βB is monotonic,and has to start at 0 and get to BB(x) at infinity,and it can't change from BB(x)-1 to BB(x) at infinity-1(because you can't have infinity-1))It is uncomputable too,since by computing it we can find a non finite upper bound of βB,to replace the uncomputableness of βB(x,inf)

So yeah,two new interesting functions,of one is uncomputable(i found those functions when trying to induce a contradiction in BB(x)(using brute force,but forgot that the tape is infinite,thus proving that βB is computable at finite y)

Where should I submit them?Were them discovered before by other people?
What should they be called?(i called the βB function the busy little beaver function and the Bβ function the unbusy beaver function)

#3 This is Cool » Nice trick » 2023-01-18 01:20:33

imcute
Replies: 0

You can use this script to detect if a number(int64) is perfect
[6,28,496,8128,33550336,8589869056, 137438691328, 2305843008139952128].includes(x)
The longs can't outrun you

#4 This is Cool » Quadratic Log Approximation » 2023-01-16 13:56:43

imcute
Replies: 0

ln(x+1)=ax^2+(ln2-a)x from 0 to 1
a is about -0.23557
the average error is 0.003388
this can be used for stuff like fast inverse fourth root or something(ln(1+x) is used on the mantissa from 0 to 1)

#5 Re: Jai Ganesh's Puzzles » 10 second questions » 2023-01-11 14:44:14

ganesh wrote:

Hi,

#8585.

Calculator or no calculator?
21

#6 Re: Help Me ! » Vector multiplication » 2023-01-10 21:31:00

You cannot multiply two vectors like when you add them.
(it is correct in a CS perspective but not in a math perspective)
Dot product is what you was wanting to do.

#7 This is Cool » Why is the night sky dark(in newtonian physics,universe not expanding) » 2023-01-07 14:03:35

imcute
Replies: 0

Why is the night sky dark?
Assume we have an infinite grid of stars spaced evenly and we are not in one of them
The brightness (and tidal forces) we get is ∑∑∑1/((i-1/2)^2+(j-1/2)^2+(k-1/2)^2)
The question is,does this converge?
If we slightly tweak our model a bit,so that the universe on a polar coordinate,and the stars form a circular pattern,and the nth layer has n stars on it,we get an harmonic series of light which is unending and still less than the 3d universe.

Call Hubble to the rescue!

#8 Re: Help Me ! » Werid linear error term on self made ln function » 2023-01-06 18:25:31

Bob wrote:

(1) What you are trying to code in words.Ln function on complex rationals

(2) The algorithm(s) you are using (or a flow diagram, for example).Second grade division method
How much times does 3 go into 12?
12-3=9
9-3=6
6-3=3
3-3=0(0 is less than 3)
4 times
How much "exponents" does 3 go into 81?
81/3=27
27/3=9
9/3=3
3/3=1(1 is less than 3)
4 times
(3) Some comment lines to make it clear what each section of code does.dk how to do that,im not a good commenter

(4) The language you are coding in.python

(5) A list of the variables, stating whether each is an integer, decimal, string etc.python is dynamicly typed

(6) A clear statement of what output you were expecting and the output you are getting.
>>>ln(e^2)#==2
1.9999999andsomeotherjunk
>>>ln(e^3)#==3
2.9999999andonepointfivetimesthatjunk
>>>(3-ln(e^3)/(2-ln(e^2))#atleast not just on the spot 1.5 right?errors are random
1.5
Bob

#9 Re: Help Me ! » Werid linear error term on self made ln function » 2022-12-31 11:19:38

The relavent code are the log function in the num class
The other functions are fine.

#11 Help Me ! » Werid linear error term on self made ln function » 2022-12-30 12:43:29

imcute
Replies: 6

https://replit.com/@imcute-aaaa/Numbers#main.py(it doesn't seem to error now cuz i added that error term)
my ln results are all less than (if i should get result x,then it will be less 0.00000000076956675x)
or you can say that all my results are multiplied by 0.99999999923043323392556634123536
but why???(It's not a precision problem!i used my complex rational class which has infinite precision and the error term does not relate to the prec parameter other than going wrong under prec<10 and its not <10)

#13 Re: Puzzles and Games » some werid and fun thing in my dream last night » 2022-12-26 22:44:52

imcute wrote:

An elegant entertaining engineer fails forcing the former to

ganesh wrote:

Grand Gallant Giver

#14 Re: Puzzles and Games » some werid and fun thing in my dream last night » 2022-12-26 18:28:11

ganesh wrote:

Grand Gallant Giver

?????????
Does not fit

#15 Re: Puzzles and Games » some werid and fun thing in my dream last night » 2022-12-26 15:23:04

ganesh wrote:

(an) Elegant Entertaining Engineer

Fails Forcing (the) Former (to)
Previous stuff:
Abnormal acute angles betray bent bells,cull cute cats,and dominate dull dashes.
An elegant entertaining engineer fails forcing the former to

#19 Puzzles and Games » some werid and fun thing in my dream last night » 2022-12-26 11:16:09

imcute
Replies: 9

p1:No Nonnegative Numbers
p2:Or Oblong Objects
p3:Painted Purple Primes.
p4:(next sentence go on with q)
Stuff that are used to keep grammar(and punchuation) do not need to start with the correct stuff
Fun and true statements are prefered.
Oh,and no politics,religion,or swearing!
I'll start:

Abnormal Acute Angles

#20 Re: This is Cool » Double Factorial » 2022-12-25 22:50:58

i made a continuation for this thing https://www.mathisfunforum.com/viewtopic.php?pid=429787#p429787 (yes u linked to it yesterday) did i do it correct?

#21 This is Cool » Double factorial » 2022-12-25 00:04:23

imcute
Replies: 1

a double factorial products up 2 at a time not 1
2x!!=product k=1->x 2x
so x+2n!!=x!!*product k=1->n 2x
for something like a gamma function,we can take the log
L(x)=ln(x!!)
N is a huge number
so ln(N+k)-ln(N)=0 for a little k compared to N
L(N+2n)=L(N)+sum k=1->n ln(N+2k)
=L(N)+sum k=1->n ln(N)
=L(N)+nlnN
now do some substitution
L(2n)+sum k=1->N/2 ln(2n+2k)=sum k=1->N/2 ln(2k)+nlnN
move it to right and merge sums
L(2n)=sum k=1->N/2 -ln(2n+2k)+ ln(2k)+nlnN
log rule
L(2n)=sum k=1->N/2 ln(k/k+n)+nlnN
sub n for 2n and exponentiate
n!!=product k=1->N/2 k/k+n/2 +N^(n/2)
minor changes
n!!=product k=1->N/2 2k/k+n +sqrt(N^n)
done!
change the limits a bit N->2N^2 x->n
x!!=lim N->inf 4*N^n*product k=1->N^2 k/(x+2k)
idk if it actually works but i think it would cuz it based on the factorial video from lines that connect

#22 Re: Coder's Corner » Comics I have drawn during boring classes » 2022-12-19 20:32:00

game wrote:

I have a suggestion. Maybe you can add a next and last page button so you can go from comic 1 to comic 2 and from comic 2 to comic 1.

u can jump to the page

#23 Re: Help Me ! » What's this? » 2022-12-14 18:00:20

i get it
one root means that the valley is at zero for a parabola looking shape
so ddx(x-logt x)=0=1-1/xlnt
so x is always logt e on valleys
logt e-logt2 e=0
logt (e/logt e)=0
e/logt e=1
elnt=1
lnt=1/e
t=e^1/e

#24 Re: Help Me ! » What's this? » 2022-12-14 17:48:48

ganesh wrote:

Hi imcute,

The approximate value of xth root of x (maximum value) for any real number is approximate value 1.444667861.

.

Oh.
Why does it also appear in that logrhythmitic equation?

#25 Help Me ! » What's this? » 2022-12-14 16:00:05

imcute
Replies: 3

t=1.44466786100976618
the root of "|x-logt x| has 1 root“

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