Ars Conjectandi

Series
Algebra Seminar
Time
Monday, October 20, 2025 - 1:00pm for 1 hour (actually 50 minutes)
Location
Skiles 005
Speaker
Manuel Kauers – Johannes Kepler University – http://www.kauers.de/
Organizer
Donggyu Kim, Julia Lindberg

Please Note: There will be a pre-seminar 10:55-11:15 in Skiles 005.

Proving conjectures is an essential part of our job as mathematicians. Another essential part is to come up with plausible conjectures. In the talk, we focus on this part. We present a new twist to an old method from computer algebra for detecting recurrence equations of infinite sequences of which only the first few terms are known. By applying this new version systematically to all the entries of the Online Encyclopedia of Integer Sequences, we detected a number of potential recurrence equations that could not be found by the classical methods. Some of these have meanwhile been proven. This is joint work with Christoph Koutschan. 

====(Below is the information on the pre-talk.)====

Titile: Lattice Reduction 
                                                                                                           
Abstract: It is well known how to go from an exact number (e.g. 1/3) into an approximation (e.g. 0.333). But how can we get back? At first glance, this seems impossible, because some information got lost during the approximation. However, there are techniques for doing this and similar seemingly magic tricks. We will discuss some such tricks that rely on an algorithm for finding short vectors in integer lattices.