it is a small surprise that, for w = Exp[ 2 Pi I /30 ] alias 1^(1/30) , w+w^7+w^8+w^18+w^19+w^25 = 0 no cancellation of symmetric pairs, triples or quintuples in sight, but w+w^7+w^19+w^25 = -w^13 (* four out of five *) and w^8+w^18 = -w^28 = +w^13 (* two out of three *) could be called "cancellation by missing parts" ;-)) Wouter Meeussen Senior Scientist nv Vandemoortele Izegem R&D Center Albertlaan 79, B8870 Izegem tel +32 (0)51 33 21 24 fax +32 (0)51 33 21 75 =============================== This email is confidential and intended solely for the use of the individual to whom it is addressed. If you are not the intended recipient, be advised that you have received this email in error and that any use, dissemination, forwarding, printing, or copying of this email is strictly prohibited. You are explicitly requested to notify the sender of this email that the intended recipient was not reached.