Can't get i from for ((i = 0; i < koniec.length; i++) to index thru console.log(silnia(5)[i]);

In my JS script, I am trying to index thru silnia() a function that returns an array, I can do that manually without a problem: silnia(5)[1] but when I try to use an i from a for-loop it does not work.

koniec = [1,2,3];

for (i = 0; i < koniec.length; i++){
    // Returns only undefined:
    console.log(silnia(5)[i]);

    // Works no problem:
    // console.log(silnia(5)[2]);
}


function silnia(n){
    var wynikSilni = [];

    for(i = 1; i < (n + 1); i++){
        wynikSilni.push(i);
    }

    return wynikSilni;    
}