Numbers by the meter - the math ruler

Albrecht Beutelspacher's math ruler. In addition to the millimeter scale, the double-sided printed meter ruler offers interesting and surprising information from the world of numbers and shapes. From Pythagoras to the Indian number genius Ramanujan, the math ruler shows the achievements of the brightest minds in mathematics. What mathematical peculiarities do the numbers have? What are the most important number ranges, number systems and formulas? From the golden section to the hectoliter, the math ruler draws an attractive arc that is aimed at everyone who is interested in numbers.