<input type="checkbox" value="1" name="double[fields1]" id="double-fields1">
<input type="checkbox" value="1" name="double[fields2]" id="double-fields2">
<input type="checkbox" value="1" name="double[fields3]" id="double-fields3">
$("#double-fields1").on("change", function(){
$("#double-fields2").prop('checked',$(this).prop('checked'));
$("#double-fields3").prop('checked',$(this).prop('checked'));
});
$("#double-fields1").on("keyup", function(){
$("#double-fields2").val($(this).val());
$("#double-fields3").val($(this).val());
});