:: deftheorem Def11 defines MAJ3 GATE_1:def 11 :
for a, b, c being set holds
( ( ( ( not a is empty & not b is empty ) or ( not b is empty & not c is empty ) or ( not c is empty & not a is empty ) ) implies MAJ3 (a,b,c) = NOT1 {} ) & ( ( not a is empty & not b is empty ) or ( not b is empty & not c is empty ) or ( not c is empty & not a is empty ) or MAJ3 (a,b,c) = {} ) );