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index.js

var pre = '<pre>*</pre>';
var txt = '';
var chars = '      xx  xxx   0000000000005550';

window.setInterval(function() {
  var txt = '';
  var c = chars.split('');
  chars = c[c.length] + c.slice(0, -1);

for (var x = 0; x < 30; x++) {
	for (var y = 0; y < 60; y++) {
    txt += chars[Math.floor(
      Math.sqrt(Math.pow(x - 14, 2) + Math.pow((y/2) - 14, 2)) * (10/8))];
  }
  txt += '\n';
}

document.getElementsByClassName('right')[0].innerHTML = pre.replace('*', txt);
  
}, 1000);