MathDB

370

Part of 1983 All Soviet Union Mathematical Olympiad

Problems(1)

ASU 370 All Soviet Union MO 1983 no of diff.segments in decimal repr.

Source:

7/28/2019
The infinite decimal notation of the real number xx contains all the digits. Let unu_n be the number of different nn-digit segments encountered in xx notation. Prove that if for some nn, un≤(n+8)u_n \le (n+8), than xx is a rational number.
decimal representationnumber theoryalgebraDigits