Is there a shorthand for an indicator function of a positive integer?

[bruno67]

Is there a convenient shorthand for an "indicator function" of a positive integer n which vanishes if n is odd and is equal to 1 otherwise? I was thinking about something like

\mathbb{1}_{\{\mathrm{mod}(n,2)=0\}}(n),
but I'm not sure if this would be considered acceptable mathematical notation.

 

[HallsofIvy]

What about
\frac{(-1)^n+ 1}{2}

 

[tiny-tim]

(1 + (-1)ⁿ)/2 ?

δ(sin(nπ)) ?

 

[bruno67]

Thanks!