deffunc H3( set , Nat) -> ManySortedSign = BitSubtracterWithBorrowStr (x . ($2 + 1)),(y . ($2 + 1)),$1;
ex S being non empty non void strict unsplit gate`1=arity gate`2isBoolean ManySortedSign ex f, h being ManySortedSet of NAT st
( S = f . n & f . 0 = 1GateCircStr <*> ,((0 -tuples_on BOOLEAN ) --> TRUE ) & h . 0 = [<*> ,((0 -tuples_on BOOLEAN ) --> TRUE )] & ( for n being Nat
for S being non empty ManySortedSign
for x being set st S = f . n & x = h . n holds
( f . (n + 1) = S +* H3(x,n) & h . (n + 1) = H1(x,n) ) ) )
from CIRCCMB2:sch 8(A1);
hence
ex b1 being non empty non void strict unsplit gate`1=arity gate`2isBoolean ManySortedSign ex f, g being ManySortedSet of NAT st
( b1 = f . n & f . 0 = 1GateCircStr <*> ,((0 -tuples_on BOOLEAN ) --> TRUE ) & g . 0 = [<*> ,((0 -tuples_on BOOLEAN ) --> TRUE )] & ( for n being Nat
for S being non empty ManySortedSign
for z being set st S = f . n & z = g . n holds
( f . (n + 1) = S +* (BitSubtracterWithBorrowStr (x . (n + 1)),(y . (n + 1)),z) & g . (n + 1) = BorrowOutput (x . (n + 1)),(y . (n + 1)),z ) ) )
; verum