MathDB
Negative Bases

Source: PRMO Leg 2 P15

August 25, 2019
algebra

Problem Statement

In base-22 notation, digits are 00 and 11 only and the places go up in powers of −2-2. For example, 1101111011 stands for (−2)4+(−2)3+(−2)1+(−2)0(-2)^4+(-2)^3+(-2)^1+(-2)^0 and equals number 77 in base 1010. If the decimal number 20192019 is expressed in base −2-2 how many non-zero digits does it contain ?
Back to ProblemsView on AoPS