let b1= 2;
let q = 7;
let n = 5;
function GeomProg(b1, q, n){
return b1 * Math.pow(q, (n - 1));
}
function ReqGeomProg(b1, q, n) {
if(n == 1) return b1;
return q * ReqGeomProg(b1, q, n - 1);
}
console.log(GeomProg(b1, q, n));
console.log(ReqGeomProg(b1, q, n));