this post was submitted on 27 Oct 2025
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cross-posted from: https://sh.itjust.works/post/48633930

Normally, we use a place-value system. This uses exponentials and multiplication.

1234
^^^^
||||
|||└ 4 * 10^0 = 4
||└ 3 * 10^1 = 30
|└ 2 * 10^2 = 200
1 * 10^3 = 1000

1000 + 200 + 30 + 4 = 1234

More generally, let d be the value of the digit, and n be the digit's position. So the value of the digit is d * 10^n^ if you're using base 10; or d * B^n^ where B is the base.

1234
^^^^
||||
|||└ d = 4, n = 0
||└ d = 3, n = 1
|└ d = 2, n = 2
d = 1, n = 3

What I came up with was a base system that was polynomial, and a system that was purely exponential, no multiplication.

In the polynomial system, each digit is d^n^. We will start n at 1.

polynomial:
1234
^^^^
||||
|||└ 4^1 = 4 in Place-Value Decimal (PVD)
||└ 3^2 = 9 PVD
|└ 2^3 = 8 PVD
1^4 = 1 PVD

1234 poly = 1 + 8 + 9 + 4 PVD = 22 PVD

This runs into some weird stuff, for example:

  • Small digits in high positions can have a lower magnitude than large digits in low positions
  • 1 in any place will always equal 1
  • Numbers with differing digits being equal!
202 poly = 31 poly
PVD: 2^3 + 2^1 = 3^2 + 1^1
8 + 2 = 9 + 1 = 10

In the purely exponential system, each digit is n^d^. This is a bit more similar to place value, and it is kind of like a mixed-base system.

1234
^^^^
||||
|||└ 1^4 = 1
||└ 2^3 = 8
|└ 3^2 = 9
4^1 = 4

1234 exp = 4 + 8 + 9 + 1 PVD = 22 PVD

However it still runs into some of the same problems as the polynomial one.

  • Small digits in high positions can have a lower magnitude than large digits in low positions (especially if the digit is 1)
  • The digit in the ones place will always equal 1
  • Numbers with differing digits can still be equal
200 exp = 31 exp
PVD: 3^2 = 2^3 + 1^1
9 = 8 + 1

So there you have it. Is it useful? Probably not. Is it interesting? Of course!

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[–] bleistift2@sopuli.xyz 5 points 3 months ago (1 children)

If anyone is wondering (like me) if every integer can be represented: OP gave the answer with

1 in any place will always equal 1

So you can trivially get any base-10 place-value number n by stringing n 1s together.

[–] DeltaWingDragon@sh.itjust.works 4 points 3 months ago

That only works in the polynomial one, and it is very trivial. Like trival^^2 (tetration).

I almost added a challenge to it, which was this:

Try to find the smallest number of symbols where you could represent any integer!

until I realized you could just use all 1s in the polynomial system, like you mentioned.

[–] bleistift2@sopuli.xyz 3 points 3 months ago* (last edited 3 months ago) (1 children)

weird stuff, for example:

  • Numbers with differing digits being equal!

We also have that in place-value systems, too. .9999… = 1. What’s weird in poly is that it happens purely in the integers.

[–] DeltaWingDragon@sh.itjust.works 2 points 3 months ago* (last edited 3 months ago) (1 children)

~~PVD stands for Place Value Decimal, which is the ordinary system we use every day. Did you mix something up?~~ fixed, no need to keep this comment up

[–] bleistift2@sopuli.xyz 1 points 3 months ago

Indeed. Thanks for pointing it out.

[–] ns1@feddit.uk 1 points 3 months ago (1 children)

I tried counting to 10 in both to get a feel for what is going on, choosing the form of each number that seemed to fit best.

In polynomial: 1 2 3 20 21 22 23 200 30 31

And in exponential: 1 2 3 20 21 22 23 30 200 201

Am I doing it right?

[–] DeltaWingDragon@sh.itjust.works 2 points 3 months ago (1 children)

Polynomial works fine.

Exponential, runs into problem 2 that I brought up.

The digit in the ones place will always equal 1

So 01, 02, 03, 04, 05... 09, 0A, 0B, 0C, 0D, 0E, 0F... will never exceed 1.

(I thought that the polynomial problem (1 in any place will always equal 1) would be worse, but it turns out the opposite is true.)

Fixed exponential count:
1, 10, 11, 20, 21, 111, 120, 30, 200, 201

Or, in the trivial^^2 case for exponential, you could just put a 1 in the highest place and put a bunch of 0s after it.
1, 10, 100, 1000, 10000...

[–] ns1@feddit.uk 1 points 3 months ago

Ah yes I see, thanks!

The next open question that comes to mind is what's the most awkward number to write in each system. Are there some that force you to either use loads of symbols or a huge number of digits? I'll leave that for everyone to think about