waybig

You can buy a Lottery ticket in the PokéMart.
Each ticket gives you 3 random numbers.

At the end of the week, 3 numbers are drawn.
The more numbers you have that match the drawn numbers, the higher the chance you win money.

Here are further details: https://wiki.pokemon-vortex.com/wiki/Lottery

Thanks Auke1993 I was curious as well.