digits in sequence of powers of 2
Source: Spanish Mathematical Olympiad 1968 P7
December 4, 2022
number theoryDigitspower of 2
Problem Statement
In the sequence of powers of (written in the decimal system, beginning with ) there are three terms of one digit, another three of two digits, another three of , four out of , three out of , etc. Clearly reason the answers to the following questions:
a) Can there be only two terms with a certain number of digits?
b) Can there be five consecutive terms with the same number of digits?
c) Can there be four terms of n digits, followed by four with digits?
d) What is the maximum number of consecutive powers of that can be found without there being four among them with the same number of digits?