[(20+113+@:4)*7-2000]:3-66+1000=1000
[(133+@:4)*7-2000]:3=1000-1000+66
[(133+@:4)*7-2000]=66*3
(133+@:4)*7=198+2000
133+@:4=2198:7
@:4=314-133
@=181*4
@=724
Verific : [(20+113+724:4)*7-2000]:3-66+1000=1000
[(20+113+181)*7-2000]:3-66+1000=1000
(314*7-2000):3-66+1000=1000
(2198-2000):3-66+1000=1000
198:3-66+1000=1000
66-66+1000=1000
1000=1000