The system that uses square roots was for generation 1-2 (which technecally had DV and Stat Exp rather than IV and EV, respectively). :P

It looks like you typed the formulas wrong, so I'll show you them proper. :P

**Gen 1-2:**

^{Anything surrounded by floor[] is rounded down. Anything surrounded by sqrt[] is square rooted. :P}

HP= floor[(((Base+IV)*2+(floor[sqrt[EV]]/4)*Level/100]+Level+10

Other Stat= floor[(Base+IV)*2+(floor[sqrt[EV]]/4)*Level/100]+5

**Gen 3+**

^{Ditto above}

HP= floor[(2*Base+IV+floor[EV/4])*Level/100]+Level+10

Other Stat= floor[(floor[(2*Base+IV+floor[EV/4])*Level/100]+5)*Nature

If the floor[]'s are too hard to follow, just remove them and round down whenever you divide and multiply by nature. :P

Conversly, replace sqrt[] with a radical. :P

Source

Hope I Helped!