Andries E. Brouwer

prof.dr. A.E. Brouwer         home:
Dept. of Math.                Bessemerstraat 21 
Techn. Univ. Eindhoven        1097 AM Amsterdam
P.O. Box 513
5600MB Eindhoven               +31-20-6942551
Netherlands

email: aeb@cwi.nl, aeb@win.tue.nl

people at win.tue.nl / owinfo / library / eiψ / eidma / diamant

Math

List of (mathematical) publications and available preprints.

Mathematicians are idiots.

Algebraic graph theory

A feeble attempt to make the files with Additions and Corrections to `Distance-Regular Graphs' by Brouwer, Cohen and Neumaier (Springer, 1989) available. The source is some troff dialect, with most formatting commands removed.

Info on email server (that stopped working mid 2004) with information on distance-regular graphs.

Spectra of graphs Some course notes. Spectra of graphs, extended course notes.

A table of parameters of strongly regular graphs.

A table of parameters of directed strongly regular graphs.

A slowly growing collection of graph descriptions.

All small (0,2)-graphs. And small integral trees. And the known cages.

(For small association schemes, see the Miyamoto-Hanaki site.)

Counts on the number of cospectral graphs on at most 12 vertices.

Random stuff inspired by Ph.D. theses of people nearby: Man, Erik, Tim, Ralf, Sander ...

Computational complexity

Finding the maximum coclique in a sparse graph. Two examples.

Coding theory

Server for bounds on the minimum distance of q-ary linear codes, q=2,3,4,5,7,8,9. Several other interfaces exist. There are instructions on how to use the email server (that stopped working mid 2004). Plots of the rates of the codes in these tables.

A small table of bounds for binary codes.

A small table of bounds for ternary codes.

A small table of bounds for quaternary codes.

A small table of bounds for 5-ary codes.

A few bounds on constant weight codes.

Computer algebra

Some preliminary lecture notes for a course Computers and Mathematics (Dutch). Includes some ancient PDP8 stuff.

Unix port of the COCO computer algebra system for computations with permutation groups.

Algebra 1

Some preliminary lecture notes for course 2F715 (Dutch).

Algebra 2

Some preliminary lecture notes for course 2F725, a.k.a. 2WF10. And a different version. (Both Dutch.)

Elliptic curves

Course 2F780 (Number theory, Elliptic curves, Cryptography).

Algebra and Geometry

Course 2WF02 / 2WF05. Contact details.

Algebraic Topology

Some preliminary lecture notes.

Cardinal and Ordinal Numbers

Very brief introduction to cardinals and ordinals.

Lattices

DAM course notes.

Quantum Computation

Topics and contact details.

Prijsvraag | Contest

Eindejaars Prijsvraag 2000 | End-of-Year Contest 2000. And a discussion of the problem.

Eindejaars Prijsvraag 2001 | End-of-Year Contest 2001.

Eindejaars Prijsvraag 2002 | End-of-Year Contest 2002.

Games and Puzzles

An applet to play a Japanese puzzle and a somewhat larger version. (In Japan this game is called "Paint by Numbers". The very good site of Mitsuhiro Kajitani doesn't seem to exist anymore.)

Remarks on how to solve Sudoku puzzles.

An applet to play a puzzle that is sometimes called Button Madness, and some numerical info. Also Lights Out! (Knuth's perfect parity patterns) with an extensive table of periods.

The 0-person game of Sandpile, or Chip Firing.

The game of Chomp. And an applet.

And a NIM applet.

Who can construct a Benjamin Franklin magic square of order 12?

Linux

Linux and other computer related information (such as a list of all known DOS partition types, or the instruction set of the 8051 microprocessor). OpenMP, the easiest way to use a multi-CPU machine.

ADSL

Installation and security of ADSL and Alcatel Speed Touch ethernet modem.

The password algorithm.

Crypto

How to decrypt the Dutch telephone CD-ROM, a story (Dutch) and programs (C)

Recht / Law

Een verzameling Nederlandse wetten.

Het proces Stern vs. Brouwer.

Levenslang voor Lucia de B vanwege foutieve kansberekening.

COS and family

Church of Scientology (sic) information - removed in 1997 on request of the TUE (that avoids legal battles), added again Dec 2005 (after Karin Spaink and XS4ALL won all legal battles), removed again in Feb 2007 on request of COS lawyers. See also XS4ALL News and Karin Spaink's page with COS material.

Some stories about Landmark Forum.