How to copy layer structure by number sequence?

This script automates the process @Sorontar has described. It requires an Illustrator action which is also included.
Required AI Action (load from "Action Panel" flyout menu: Load Actions)

dupLayerTest.ai (Use to test script) 

/**
• by Ray Craighead
• 'dupLayer' Function will duplicate first layer of active document "x" number of times numbering each layer sequentially.
• Requires Illustrator Action: Paste_Deselect, provided separately in .aia file.
• First layer in AI file must be named with a number.
**/
function dupLayer() {
    var aDoc = app.activeDocument;
    //deselect all
    selection = null;
    //Set number of layers required
    layerCount = prompt('Set number of layers', 20)
    //Capture name of top layer of current document in variable "layerName"
    var layerName = aDoc.layers[0].name;
    //Set variable "myLayer" to layer by that name
    var myLayer = aDoc.layers.getByName(layerName);
    //Select everything on "myLayer" (required for Action run with "doScript")
    myLayer.hasSelectedArtwork = true;
    //Copy selection to system clipboard
    app.copy();
    //loop through layers until layers equal more than "layerCount"
    while (aDoc.layers.length < layerCount) {
        myLayer.name = 'x';
        //doScript requires Illustrator Action "Paste_Deselect" in Action Folder: "AI Actions_KM_2"
        app.doScript("Paste_Deselect", "test");
        selection = null;
        //Set 2nd layer name to "layerName"
        aDoc.layers[1].name = layerName;
        //Set top layer name to "layerName + 1" (parseFloat function converts "layerName" to a number )
        aDoc.layers[0].name = parseFloat(layerName) + 1;
        layerName = aDoc.layers[0].name;
    }
    aDoc.layers[aDoc.layers.length-1].name = 1;
}
dupLayer();