The Skolem Problem: a century-old enigma at the heart of computation
Joël Ouaknine
Max Planck Institute for Software Systems
04 Feb 2026, 12:15 pm - 1:15 pm
SaarbrĂĽcken building E1 5, room 002
Joint Lecture Series
It has been described as the most important problem whose decidability is still
open: the Skolem Problem asks how to determine algorithmically whether a given
integer linear recurrence sequence (such as the Fibonacci numbers) has a zero
term. This deceptively simple question arises across a wide range of topics in
computer science and mathematics, from program verification and automata theory
to number theory and logic. This talk traces the history of the Skolem Problem:
from the early 1930s to the current frontier of one of the most enduring open
questions in computer science.
It has been described as the most important problem whose decidability is still
open: the Skolem Problem asks how to determine algorithmically whether a given
integer linear recurrence sequence (such as the Fibonacci numbers) has a zero
term. This deceptively simple question arises across a wide range of topics in
computer science and mathematics, from program verification and automata theory
to number theory and logic. This talk traces the history of the Skolem Problem:
from the early 1930s to the current frontier of one of the most enduring open
questions in computer science.