MAYBE

Problem:
 1024() -> 1024_1(0())
 1024_1(x) -> if(lt(x,10()),x)
 if(true(),x) -> double(1024_1(s(x)))
 if(false(),x) -> s(0())
 lt(0(),s(y)) -> true()
 lt(x,0()) -> false()
 lt(s(x),s(y)) -> lt(x,y)
 double(0()) -> 0()
 double(s(x)) -> s(s(double(x)))
 10() -> double(s(double(s(s(0())))))

Proof:
 Open