by Thomas Taylor, A. J. Valpy
Number of pages: 286
Theoretic arithmetic, in three books: containing the substance of all that has been written on this subject by Theo of Smyrna, Nicomachus, Iamblichus, and Boetius, together with some remarkable particulars respecting perfect, amicable, and other numbers, which are not to be found in the writings of any ancient or modern mathematicians. Likewise, a specimen of the manner in which the Pythagoreans philosophized about numbers, and a development of their mystical and theological arithmetic.
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by Wissam Raji - The Saylor Foundation
These are notes for an undergraduate course in number theory. Proofs of basic theorems are presented in an interesting and comprehensive way that can be read and understood even by non-majors. The exercises broaden the understanding of the concepts.
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 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.