:: deftheorem Def22 defines the_left_argument_of MODELC_1:def 22 :
for H being CTL-formula st ( H is conjunctive or H is ExistUntill ) holds
for b₂ being CTL-formula holds
( ( H is conjunctive implies ( b₂ = the_left_argument_of H iff ex H1 being CTL-formula st b₂ '&' H1 = H ) ) & ( not H is conjunctive implies ( b₂ = the_left_argument_of H iff ex H1 being CTL-formula st b₂ EU H1 = H ) ) );