Great! Thanks you all, mates, for a constructive answers!

That exactly what I have thought and want to use with the profit. Means that, as the speed of my hardware is only ~25 MKey/s I have not enough of my life to check all that range and, asuming that three quarters of addresses have already been checked, I will better focuse only on the last quarter.

Thanks, bro! Soon I will share with you my reward