Demonstration of write/writeln functions and for loop

The JavaScript code:

document.writeln('<p>Odd integers from 1 to 100:'); var sum = 0; for (var i=1; i<=100; i+=2) { document.write('  ' + i); sum += i; } document.writeln('</p>'); document.writeln('<p>The sum is: ' + sum + '</p>');