const num = 5;
const full = num*2;
const last = full-1;

let topHalf = "";
let bottomHalf = "";

for (let i = 1, j = last; i < j; i += 2, j-=2) {
  let strinz = `${i}`.repeat(i);
  let speiz = ' '.repeat(Math.floor((num-i)/2));
  topHalf += speiz + strinz + speiz + '\n';
  bottomHalf = speiz + strinz + '\n' + bottomHalf + speiz;
}

const isOdd = !!(num%2);
const median = (isOdd) ? `${num}`.repeat(num) + '\n' : '';

console.log(topHalf + median + bottomHalf);