@Joe Riel ,
@ acer25364 is much more suited to my need. Thanks though

@acer thank you very much for the prompt response. It came out as intended

@acer I am getting this error message when I copy and paste your lines "Error, invalid `$` operator". I don't know if it has something to do with the edition I am using (maple 18). Besides I can't see where nops(L3) came from

@Carl Love your coding style interests me. Could you dm me on joriuch@yahoo.com?

@tomleslie Thank you very much, it worked perfectly well