If a girl rejects me, about how many days should i wait before asking her out again?

you should double the time every time you ask her out.

so it will be like you ask her she says no and then you wait 1 minute

ask her again ,are you sure thinks will be great if we give it a chance. if no double the time now 2 min.

next 4 next, 8 next, 16 next, 32 next, 1 hour 4 min. then 2 hour 8 minutes.

this is how modems also works they keep checking and for every no response they increase the time such that they don't jam the network.

and you will always have the hope that maybe next time she may say yes.

let's say your time has reached the rejection level of 1 year you can work on yourself mean while and after 1 year again approach her.

if rejected again you will get 2 years keep earning keeping getting smart and again approach her.

what happens is that sometimes stupid looking people in high school or college later become so hot and sexy in life.

so this "additive increase and multicative decrease" will help.

The older she gets, the more likely she’ll get desperate and end up alone.

It’s definitely an exponential curve in your favor... assuming your curve doesn’t go the opposite way over the same period of time...