What is the largest real number one can write within 200 characters?

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Discussion Overview

The discussion revolves around the challenge of expressing the largest real number possible within a limit of 200 characters. Participants explore various mathematical notations and functions while adhering to specific rules regarding character count and the definition of real numbers.

Discussion Character

  • Exploratory
  • Debate/contested
  • Mathematical reasoning

Main Points Raised

  • Some participants propose using Knuth's up-arrow notation to express large numbers, with varying numbers of arrows suggested.
  • Others suggest using factorials of Graham's number, with discussions on the implications of factorial notation.
  • A participant mentions using the expression involving the tangent function to approach large values, noting the complexity of determining its size relative to others.
  • There is a debate on whether more arrows in notation necessarily lead to larger numbers, with some expressing uncertainty about the definitions involved.
  • Participants discuss the limitations of expressing numbers within the character count and the potential for inventing shorthand notations to circumvent these limits.
  • Some express skepticism about the ability to determine a definitive largest number due to the nature of mathematical expressions and the rules of the challenge.

Areas of Agreement / Disagreement

Participants generally do not reach a consensus on which number is the largest, with multiple competing views and expressions presented throughout the discussion.

Contextual Notes

Limitations include the challenge of defining real numbers and the constraints of character count, which may affect the expressions used. The discussion also highlights the complexity of comparing large numbers expressed in different notations.

  • #31
It is insane. As long as we deal with numbers that can be expressed either directly or using logarithmic scales I have no problems comparing orders of magnitude (and guessing which number is larger, or trying to somehow evaluate their values). But I fell so hopelessly lost when it comes to hyperoperations :eek:
 
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  • #32
The product of all the numbers except this one that have been and will be posted on this thread raised to the power of that same number that same number of times.
 
  • #33
epenguin said:
all the numbers except this one that have been and will be posted

No way.

micromass said:
- No references to earlier posts allowed.

But you can take a product only of all numbers that WILL be posted to stay in accordance with the rules :wink:
 
  • #34
Borek said:
But you can take a product only of all numbers that WILL be posted to stay in accordance with the rules :wink:

And since I will post ##0##, that is not a good idea.
 
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  • #35
micromass said:
And since I will post ##0##, that is not a good idea.

The product of the factorials of (the absolute values of) all the numbers that will be posted, then. :D
 
  • #36
Ben Niehoff said:
The product of the factorials of (the absolute values of) all the numbers that will be posted, then. :D
So I'll post ## \infty ##!:biggrin:
 
  • #37
A(G,G),

where A is the Ackermann function and G is Graham's number.
 
  • #38
Ben Niehoff said:
A(G,G),

where A is the Ackermann function and G is Graham's number.

Why stop there?
A(A(G,G),A(G,G))
is only 16 characters. If you include definitions...
A=Ackermann function
G=Gram's number
A(A(G,G),A(G,G))
Now it's still only up to 51, so, by expanding on the same idea and being slightly more concise with the explanation you can get...
Ackermann function
Gram's number
G↑↑A(A(A(A(A(A(G,G),A(G,G)),A(A(G,G),A(G,G))),A(A(A(G,G),A(G,G)),A(A(G,G),A(G,G)))),A(A(A(A(G,G),A(G,G)),A(A(G,G),A(G,G))),A(A(A(G,G),A(G,G)),A(A(G,G),A(G,G))))),A(G,G))
Which by my count comes to 200 characters, including spaces.
 
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  • #39
Or...
Ackermann function
Gram's number
B(n,x)=A performed recursively n times with arguments x. I.E. B(2,3)=A(A(3,3),A(3,3))
C(n,x)=B performed recursively n times with arguments x.
C(C(G,G),C(G,G))
 
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  • #40
Code:
f(x)=10^x!
f(f(f(f(f(f(f(f(f(f(f(f(f(f(f(f(f(f(f(f(f(f(f(f(f(f(f(f(f(f(f(f(f(f(f(f(f(f(f(f(f(f(f(f(f(f(f(f(f(f(f(f(f(f(f(f(f(f(f(f(f(f(f(9)))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))
 
  • #41
ChrisVer said:
Code:
f(x)=10^x!
f(f(f(f(f(f(f(f(f(f(f(f(f(f(f(f(f(f(f(f(f(f(f(f(f(f(f(f(f(f(f(f(f(f(f(f(f(f(f(f(f(f(f(f(f(f(f(f(f(f(f(f(f(f(f(f(f(f(f(f(f(f(f(9)))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))

This is still dwarfed by Grahams number though...
 
  • #42
micromass said:
This is still dwarfed by Grahams number though...
maybe... I haven't seen that number...
But if it's big I could try to put it in the f(f(...f(f(G))...)), and in place of 10 in 10^x! : G^x!
 
  • #44
G^G↑G^GG^G, where G is Graham's number.
 
  • #46
micromass said:
I'm afraid that doesn't beat the hugeness of the Ackerman function. https://en.wikipedia.org/wiki/Ackermann_function
Indeed. So I looked at mrspeedybob's post and cut a few characters out so I could fit in exponents for the arguments of C. Microsoft Word says it's 200 characters exactly including spaces:

Ackermann func.
Graham's #
B(n,x)=A performed recursively n times with args x. I.E. B(2,3)=A(A(3,3),A(3,3))
C(n,x)=B performed recursively n times with args x.
C(C(GC(G,G),GC(G,G)),C(GC(G,G),GC(G,G)))
 
  • #47
11
 
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  • #48
0

As I think most of the universe is empty space, 0 pretty much sums it all up.
This is probably incorrect on many levels, but I like the idea.
 
  • #49
-1/12
 
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  • #50
∞-1
 
  • #51
rootone said:
∞-1

In which number system are you working when you say ##\infty## ?
 
  • #52
nolxiii said:
11

also, to clarify, this number is not written in base ten but in some much larger base size
 
  • #53
nolxiii said:
also, to clarify, this number is not written in base ten but in some much larger base size

Then you need to specify the base in your description.
 
  • #54
micromass said:
In which number system are you working when you say ##\infty## ?
Lets say binary for simplicity, although I do realize that that a computer memory containing the number would require an infinite number of bits.
 
  • #55
no one else specified their base size
 
  • #56
nolxiii said:
no one else specified their base size

Do we really need to specify that 100% of humans nowadays work standard in base 10?
 
  • #57
rootone said:
Lets say binary for simplicity, although I do realize that that a computer memory containing the number would require an infinite number of bits.

But ##\infty## is not a real number. So what kind of number is it? How is it defined?
 
  • #58
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  • #59
what would happen in case I write:
Code:
lim_[n ->0] 1/n^2
??
 
  • #60
ChrisVer said:
what would happen in case I write:
Code:
lim_[n ->0] 1/n^2
??

Not a real number.
 

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