Main question is, how can we guess the first few digits? If even if we guess the 4 first digits correctly, the fifth digit would cause a problem if we make a mistake.
sincerely i have not investigated much in this technique, due to lack of time.
I only know that dividing by 5 with this technique, you will not worry about floating numbers.
I have applied the technique in 2 rounds and everything seems to be on the right track.
honestly do not know how many rounds are possible, but in my opinion it is a good idea.
x=2000000000000000
t=1185429467683753
A0=x-t
>>814570532316247
A1=t/5
>>237085893536750.6
A2=A0/5
>>162914106463249.4
A3=t-A1
>>948343574147002.4
A4= A0-A2
>>651656425852997.6
A5=A4-A1
>>785429467683753
A6=A3-A2
>>414570532316247
#---------------------------
t=A5
>>785429467683753
A0=A6
>>414570532316247
A1=t/5
>>157085893536750.6
A2=A0/5
>>82914106463249.4
A3=t-A1
>>628343574147002.4
A4= A0-A2
>>331656425852997.6
A5=A3-A2
>>545429467683753
A6=A4-A1
>>414570532316247
we obtain.
target=1185429467683753
R= 545429467683753