1, 3, 8, 120, ... - http://www.weburbia.demon.co.uk/pg/diophant.htm Sets of numbers such that the product of any two is one less than a square. Diophantus found the rational set 1/16, 33/16, 17/4, 105/16; Fermat the integer set 1, 3, 8, 120.

Diophantine m-tuples - http://www.math.hr/~duje/dtuples.html Sets with the property that the product of any two distinct elements is one less than a square. Notes and bibliography by Andrej Dujella.

Diophantus Quadraticus - http://www.bioinfo.rpi.edu/~zukerm/cgi-bin/dq.html On-line Pell Equation solver by Michael Zuker.

Egyptian Fractions - http://www.ics.uci.edu/~eppstein/numth/egypt/ Lots of information about Egyptian fractions collected by David Eppstein.

Fermat's Method of Infinite Descent - http://sweb.uky.edu/~jrbail01/fermat.htm Notes by Jamie Bailey and Brian Oberg. Illustrates the method on FLT with exponent 4.

Hilbert's Tenth Problem - http://www.ltn.lv/~podnieks/gt4.html Given a Diophantine equation with any number of unknowns and with rational integer coefficients: devise a process, which could determine by a finite number of operations whether the equation is solvable in rational integers.

Hilbert's Tenth Problem - http://logic.pdmi.ras.ru/Hilbert10/ Statement of the problem in several languages, history of the problem, bibliography and links to related WWW sites.

Linear Diophantine Equations - http://www.thoralf.uwaterloo.ca/htdocs/linear.html A web tool for solving Diophantine equations of the form ax + by = c.

MAGMA program - http://www.math.leidenuniv.nl/~tengely/main2.html MAGMA code to solve Diophantine equations of the form F(x)=G(y), for which Runge's condition is satisfied. Created by Szabolcs Tengely.

Pell's Equation - http://www.ieeta.pt/~tos/pell.html Record solutions.

Pythagorean Triples in JAVA - http://home.foni.net/~heinzbecker/pythagoras.html A JavaScript applet which reads a and gives integer solutions of a^2+b^2 = c^2.

Pythagorean Triplets - http://www.faust.fr.bw.schule.de/mhb/pythagen.htm A Javascript calculator for pythagorean triplets.

Quadratic Diophantine Equation Solver - http://www.alpertron.com.ar/QUAD.HTM Dario Alpern's Java/JavaScript code that solves Diophantine equations of the form Ax^2 + Bxy + Cy^2 + Dx + Ey + F = 0 in two selectable modes: "solution only" and "step by step" (or "teach") mode. There is also a link to his description of the solving methods.

Rational Triangles - http://grail.cba.csuohio.edu/~somos/rattri.html Triangles in the Euclidean plane such that all three sides are rational. With tables of Heronian and Pythagorean triples.

Solving General Pell Equations - http://hometown.aol.com/jpr2718/pelleqns.html John Robertson's treatise on how to solve Diophantine equations of the form x^2 - dy^2 = N.

The Erdos-Strauss Conjecture - http://math.uindy.edu/swett/esc.htm The conjecture states that for any integer n > 1 there are integers a, b, and c with 4/n = 1/a + 1/b + 1/c, a > 0, b > 0, c > 0. The page establishes that the conjecture is true for all integers n, 1 < n <= 10^14. Tables and software by Allan Swett.

Thue Equations - http://finanz.math.tu-graz.ac.at/~cheub/thue.html Definition of the problem and a list of special cases that have been solved, by Clemens Heuberger.

computing equal sums of like powers

Computing Minimal Equal Sums Of Like Powers - http://euler.free.fr/ Jean-Charles Meyrignac's distributed-computing project on equal sums of like powers and the place to look for the current status of the problem.

Equations Involving Sums of Powers - http://www.glasgowg43.freeserve.co.uk/sumintro.htm Joseph McLean's investigations into those equations.

Overview of Mathematician Secret Room - http://www.asahi-net.or.jp/~KC2H-MSM/mathland/overview.htm Page keeping track of solutions of x^3+y^3+z^3 < 1000 and x^3+y^3+2*z^3 < 1000.

Power Page - http://www.uwgb.edu/dutchs/RECMATH/rmpowers.htm Steve Dutch's page about powers of numbers.

Sortedsums - http://cr.yp.to/sortedsums.html D. J. Bernstein's collection of tools for enumerating small solutions to certain types of equal sums of like powers.

Taxicab Numbers - http://pi.lacim.uqam.ca/eng/problem_en.html David W. Wilson's list of the smallest number that can be expressed as a sum of two positive cubes in n different ways, for n = 1 through 5.

The Fifth Taxicab Number is 48988659276962496 - http://www.cs.uwaterloo.ca/journals/JIS/wilson10.html David W. Wilson's article on his search for the smallest integer that can be expressed as a sum of two positive cubes in 5 distinct ways, up to order of summands.

Tom's Mathematical Things - http://tom.womack.net/maths/dissert_abstract.htm Dissertation about equal sums of like powers by Tom Womack.

EAGER Activities - http://euclid.mathematik.uni-kl.de/activities/ European Algebraic Geometry Research Training Network. Activities of or related to the network.

Equivariant Intersection Theory - http://www.mimuw.edu.pl/~alan/html/Lukecin05.html 28th Autumn School in Algebraic Geometry. Lukecin, Poland; 11--17 September 2005.

GAEL - Géometrie Algébrique En Liberté - http://euclid.mathematik.uni-kl.de/~gael/ A series of conferences particularly designed for researchers in Algebraic Geometry at the beginning of their scientific career.

GAEL XIII - http://www-euclid.mathematik.uni-kl.de/~gael/GaelXIII/GaelXIII.html CIRM (Centre International de Rencontres Mathématiques), Luminy, Marseille, France; 21--25 March 2005.

Géométrie Algébrique en Liberté - http://www-euclid.mathematik.uni-kl.de/~gael/ A series of conferences aimed at researchers in Algebraic Geometry at the beginning of their scientific career.

MEGA 2005 - http://www.dm.unipi.it/MEGA05/ The Eighth International Symposium on Effective Methods in Algebraic Geometry. Computing in and with algebraic geometry: Theory, Algorithms, Implementations, Applications. Porto Conte, Alghero, Sardinia,Italy; 26 May -- 2 June 2005.

Summer Institute in Algebraic Geometry - http://www.math.princeton.edu/~rahulp/seattle05.html Three one-week sessions: Interactions with physics; Classical geometry; Arithmetic geometry. University of Washington, Seattle, WA, USA; 25 July -- 12 August 2005.

Trento Schools - http://euclid.mathematik.uni-kl.de/activities/trento.html Intended for European doctoral students and post-doctoral fellows in algebraic geometry.

VBAC Meetings - http://www.mi.uni-erlangen.de/~forkel/vbac/meetings.html Past and future meetings on Vector Bundles on Algebraic Curves.