<<< native [ EUnderover False (ESymbol Op "\8898") (EGrouped [ EIdentifier "i" , ESymbol Rel "=" , ENumber "0" ]) (EIdentifier "\8734") , EGrouped [ EIdentifier "A" , ESymbol Bin "\8745" , EIdentifier "B" ] ] >>> eqn union from {i = 0} to inf {A \[u2229] B}