var pingPong = function(i) {
  if ((i % 3 === 0) && (i % 5 != 0)) {
    return "ping";
  } else if ((i % 5 === 0) && (i % 6 != 0)) {
    return "pong";
  } else if ((i % 3 === 0) && (i % 5 === 0)) {
    return "ping pong";
  } else {
    return false;
  }
};

$(function() {
  $("#game").submit(function(event) {
    $('#outputList').empty();

    var number = parseInt($("#userNumber").val());

    for (var i = 1; i <= number; i += 1) {
      if (i % 15 === 0) {
        $('#outputList').append("<li>ping pong</li>");
      } else if ((winner) && (i % 5 != 0)) {
        $('#outputList').append("<li>ping</li>");
      } else if ((winner) && (i % 3 != 0)) {
        $('#outputList').append("<li>pong</li>");
      } else {
        $('#outputList').append("<li>" + i + "</li>");
      }
    }
    event.preventDefault();
  });
});

@@ -29,33 +29,33 @@
 %0A  if ((i %25 
-3
+5
  === 0) 
 && (i %25 5 !=
@@ -46,180 +46,43 @@
  0) 
-&&
+%7C%7C
  (i %25 
-5 != 0)) %7B%0A    return %22ping%22;%0A  %7D else if ((i %25 5 === 0) && (i %25 6 != 0)) %7B%0A    return %22pong%22;%0A  %7D else if ((i %25 3 === 0) && (i %25 5 === 0)) %7B%0A    return %22ping pong%22
+3 === 0)) %7B%0A    return true
 ;%0A  
@@ -397,33 +397,20 @@
 if (
-(winner) && (i %25 5 !
+i %25 3 ==
 = 0)
-)
  %7B%0A 
@@ -479,33 +479,20 @@
 if (
-(winner) && (i %25 3 !
+i %25 5 ==
 = 0)
-)
  %7B%0A 

Change spec test back to true/false, rewrite loop for better clarity of changes