Interesting variation on the Ulam prime number spiral. Includes downloadable Windows Visual Basic .NET application that can be used to plot Ulam’s spiral and corresponding patterns in other regular polygons.
September 9, 2006 -- From Chris, a parent, from Goole, Yorkshire, England, who is not affiliated with the site.
Interesting site comprising a list of prime numbers up to the 147121206th prime number. Lists of squares cubes etc., and a number cruncher where you enter a number and its properties are returned. It also gives the same number in binary, octal, hexadecimal, Roman, Egyptian, Chinese and Babylonian numerals.