diff --git a/IPython/frontend/html/notebook/static/js/notebook.js b/IPython/frontend/html/notebook/static/js/notebook.js
index a394747..9a80426 100644
--- a/IPython/frontend/html/notebook/static/js/notebook.js
+++ b/IPython/frontend/html/notebook/static/js/notebook.js
@@ -302,7 +302,8 @@ var IPython = (function (IPython) {
         // TODO: Bounds check for i
         var i = this.index_or_selected(index);
         var cell = new IPython.CodeCell(this);
-        cell.set_input_prompt(this.next_prompt_number);
+        // cell.set_input_prompt(this.next_prompt_number);
+        cell.set_input_prompt();
         this.next_prompt_number = this.next_prompt_number + 1;
         this.insert_cell_before(cell, i);
         this.select(this.find_cell_index(cell));
@@ -314,7 +315,8 @@ var IPython = (function (IPython) {
         // TODO: Bounds check for i
         var i = this.index_or_selected(index);
         var cell = new IPython.CodeCell(this);
-        cell.set_input_prompt(this.next_prompt_number);
+        // cell.set_input_prompt(this.next_prompt_number);
+        cell.set_input_prompt();
         this.next_prompt_number = this.next_prompt_number + 1;
         this.insert_cell_after(cell, i);
         this.select(this.find_cell_index(cell));