How can I use mathematical symbols to indicate if a number is an integer or not?

[strokebow]

Hi,

I want to be able to say the following with mathematical symbols;

1) A is any integer.
2) A is a non-integer (not a whole number).

Please help.

Thanks

 

[arildno]

For example:
1) A\in\mathcal{Z}
2) A\notin\mathcal{Z}

 

[economicsnerd]

A is an integer: A\in\mathbb Z.
A is not an integer: A\notin\mathbb Z.
A is a real number which is not an integer: A\in\mathbb R\backslash\mathbb Z.
A is not a whole number: A\notin\mathbb Z_+.