Textbook covering following topics: compositions and partitions; arithmetic functions; distribution of primes; irrational numbers; congruences; diophantine equations; combinatorial number theory; and geometry of numbers.

A web article with a brief history and account of their relationship with the Riemann zeta function and Fermat's Last Theorem (HTML/PS).

Interactive (Javascript) expression of a number as a sum of two squares.

The 196 Palindrome Quest and The Most Delayed Palindromic Number, by Jason Doucette.

A paper by David M. Russinoff describing the use of the Boyer-Moore theorem prover in mechanically generating a proof of the Law of Quadratic Reciprocity. PS/PDF.

Some notes from the MIT collection. Includes Gosper's algorithms for CF arithmetic.

With notes on Carmichael numbers and the life of R.D. Carmichael.

Maple worksheets, lecture notes and links to other resources by John Cosgrove.