let a1, a2, a3, a4, a5, a6 be object ; :: thesis: rng <*a1,a2,a3,a4,a5,a6*> = {a1,a2,a3,a4,a5,a6}
thus rng <*a1,a2,a3,a4,a5,a6*> = (rng <*a1,a2,a3,a4,a5*>) \/ (rng <*a6*>) by FINSEQ_1:31
.= {a1,a2,a3,a4,a5} \/ (rng <*a6*>) by CIRCCMB3:14
.= {a1,a2,a3,a4,a5} \/ {a6} by FINSEQ_1:39
.= {a1,a2,a3,a4,a5,a6} by ENUMSET1:15 ; :: thesis: verum