Так работает...
<!DOCTYPE html>
<html lang="en">
<head>
<title>Rainebow Balls</title>
<script src="https://ajax.googleapis.com/ajax/libs/jquery/3.1.0/jquery.min.js"></script>
</head>
<body>
<canvas id='canvas' width="800" height="800"></canvas>
<input class="corners" type="range" min="1" max="60" step="1" value="48">
<span>show</span>
<script>
var corners = $('.corners');
var num = $('span');
var a = corners.val();
$(function(){
num.text(a);
$('.corners').change(function(){
a = corners.val();
console.log(a + " =a");
num.text(a);
nov = showResalt + 2;
})
})
var showResalt = Number (a);
console.log( showResalt + 'my_range');
//console.log(nov + " = nov");
</script>
</body>
</html>