Symbol of Natural numbers

I have been commonly using $\mathbb {N}$ and $\mathbb {Z}^{+}$ to denote natural numbers. Recently I have come across on some questions the symbol $\mathbb {I}$ . I have checked various websites and have not found anything to do with the I symbol. Is it a proper symbol? I will be glad to know. Probably, it is used elsewhere in the world and I am unaware.

#NumberTheory #NaturalNumbers #Symbol

Easy Math Editor

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Remember to wrap math in `$` ... `$` or `\[` ... `\]` to ensure proper formatting.
`2 \times 3`	$2 \times 3$
`2^{34}`	$2^{34}$
`a_{i-1}`	$a_{i-1}$
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`\boxed{123}`	$\boxed{123}$

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$\mathbb{I}$ is used in India along with $mathbb{N}$ and $\mathbb{Z}^{+}$ to represent Natural numbers .

But as far as official use is considered , $mathbb{N}$ would be my choice .

A Former Brilliant Member - 5 years, 8 months ago

Isn't this the symbol for an ideal? click here

Bogdan Simeonov - 5 years, 8 months ago

I've not see $\mathbb{I}$ for ideals. They are often just $I$ or $J$ .

Calvin Lin Staff - 5 years, 8 months ago

Oh yeah, it does look different, I thought it was the normal capital I.

Bogdan Simeonov - 5 years, 8 months ago

Nope, not as far as I know. I try to refrain from using $\mathbb{N}$ unless it looks super ugly otherwise, to avoid any confusion. I take $\mathbb{N} = \mathbb{Z}^{+} \cup \lbrace 0 \rbrace$ as per the Peano axioms.

Jake Lai - 5 years, 8 months ago

The formal definition of natural numbers exclude 0.

Joel Tan - 5 years, 8 months ago

Really?

Jake Lai - 5 years, 7 months ago

Math	Appears as
Remember to wrap math in `\(` ... `\)` or `\[` ... `\]` to ensure proper formatting.
`2 \times 3`	$2 \times 3$
`2^{34}`	$2^{34}$
`a_{i-1}`	$a_{i-1}$
`\frac{2}{3}`	$\frac{2}{3}$
`\sqrt{2}`	$\sqrt{2}$
`\sum_{i=1}^3`	$\sum_{i=1}^3$
`\sin \theta`	$\sin \theta$
`\boxed{123}`	$\boxed{123}$