JSFiddle - React, Tailwind, and code Playground

by Arshad Muhammed

HTML

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JavaScript

var n = 5,
  i, j, diff = n - 1,
  temp;

for (i = 1; i <= n; i++) {

  for (j = 1; j <= i; j++) {

    if (j == 1) {

      temp = i;
      document.write(i);

    } else {
      temp = temp + diff;
      document.write(temp);
      diff = diff - 1;

    }

    document.write(' ');

  }

  diff = n - 1;
  document.write('<br>');

}