Elementary Theory of Numbers
by Waclaw Sierpinski
Publisher: ICM 1964
Number of pages: 516
The variety of topics covered here includes divisibility, diophantine equations, prime numbers (especially Mersenne and Fermat primes), the basic arithmetic functions, congruences, the quadratic reciprocity law, expansion of real numbers into decimal fractions, decomposition of integers into sums of powers, some other problems of the additive theory of numbers and the theory of Gaussian integers.
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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 William Edwin Clark - University of South Florida
One might think that of all areas of mathematics arithmetic should be the simplest, but it is a surprisingly deep subject. It is assumed that students have some familiarity with set theory, calculus, and a certain amount of mathematical maturity.
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.
by W W L Chen - Macquarie University
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.