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.

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TopNewest\(\mathbb{I}\) 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 . – Azhaghu Roopesh M · 1 year, 8 months ago

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Isn't this the symbol for an ideal? click here – Bogdan Simeonov · 1 year, 8 months ago

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– Calvin Lin Staff · 1 year, 8 months ago

I've not see \( \mathbb{I} \) for ideals. They are often just \(I\) or \(J\).Log in to reply

– Bogdan Simeonov · 1 year, 8 months ago

Oh yeah, it does look different, I thought it was the normal capital I.Log in to reply

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 · 1 year, 8 months ago

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– Joel Tan · 1 year, 8 months ago

The formal definition of natural numbers exclude 0.Log in to reply

Really? – Jake Lai · 1 year, 8 months ago

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