Combine onload and onresize (jQuery)

You can bind to the resize event alone, and trigger this event automatically upon load:

// Bind to the resize event of the window object
$(window).on("resize", function () {
    // Set .right's width to the window width minus 480 pixels
    $(".content .right").width( $(this).width() - 480 );
// Invoke the resize event immediately
}).resize();

The last .resize() call will run this code upon load.