Could you be more specific about your requirement?
How exactly,the report definition is being showcased ?
If the report is being embedded in Repeat Tree grid, then with OOB option, row number can be enabled. If the report definition is executed as stand alone, then use the following approach
1)Introduce new custom control that outputs the page list subscript
2)Add a new column to the report definition (should be first column) and assign it to any property you want
3)Change the column to be formatted with new control