Elementary Number Theory
by W W L Chen
Publisher: Macquarie University 2003
Number of pages: 98
An introduction to the elementary techniques of number theory: division and factorization, arithmetic functions, congruences, quadratic residues, sums of integer squares, elementary prime number theory, Gauss sums and quadratic reciprocity.
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by Thomas Taylor, A. J. Valpy
The substance of all that has been written on this subject by Nicomachus, Iamblichus, and Boetius, together with some particulars respecting perfect, amicable, and other numbers, which are not to be found in the writings of modern mathematicians.
by Waclaw Sierpinski - ICM
The variety of topics covered here includes divisibility, diophantine equations, prime numbers, the basic arithmetic functions, congruences, the quadratic reciprocity law, expansion of real numbers into decimal fractions, and more.
by Allen Hatcher - Cornell University
An introductory textbook on elementary number theory from a geometric point of view, as opposed to the strictly algebraic approach. A fair amount of the book is devoted to studying Conway's topographs associated to quadratic forms in two variables.
by Joseph H. Silverman - Pearson Education, Inc.
Introductory undergraduate text designed to entice non-math majors into learning some mathematics, while at the same time teaching them how to think mathematically. The exposition is informal, with a wealth of examples that are analyzed for patterns.