The Quality of Numbers One to Thirty-one
In these essays – one for each day of the month – Held demonstrates the fascinating qualities and associations, both cultural and scientific, of the first 31 integers. His ‘excursions into the realm of number’ visit such varied calling-points as the eleven-year sunspot cycle, humans’ 23 pairs of chromosomes, Snow White’s seven dwarves and Judas’ 30 pieces of silver.
Number Treasury 3
Investigations, Facts and Conjectures About More than 100 Number Families
Written as a resource for both teachers and students, this enlarged third edition of Number Treasury is designed to guide readers through the steps that will help them to think critically, to provide explanations and to formulate conjectures about different families of positive integers. Its 137 exercises and 28 'investigations', at three levels of difficulty, cover such intriguing topics as magic squares, palindromic numbers and twin primes. Detailed solutions are provided at the back of the book.