Raphaël HENRY

$$\mathcal{A}=\left\lbrace 1,2 \right\rbrace$$

I just defended my PhD in mathematics under the supervision of Nicolas Bédaride and Étienne Moutot in the GDAC team of I2M, at Aix Marseille Université.

My main subject of interest is symbolic dynamics/combinatorics on words. I study the following things:
  • Substitutive dynamical systems (morphic sequences, substitution subshifts, S-adic systems)
  • The Oldenburger-Kolakoski sequence and related problems
  • The factor complexity of sequences, mostly in 1D, sometimes in 2D
  • Ergodic theory for symbolic dynamical systems
  • Decidability and computability questions related to the previous topics

Papers

Properties of smooth sequences over even and odd alphabets
Joint work with Julien Cassaigne (in preparation)

The complexity of smooth words over binary alphabets
Joint work with Julien Cassaigne
Preprint ARXIV

On the minimal components of substitution subshifts
Published in Theoretical Computer Science TCS ARXIV

Morphic Sequences: Complexity and Decidability
Published in Electronic Proceedings in Theoretical Computer Science ARXIV

PhD thesis

Minimalité et complexité pour les substitutions et les mots lisses
THESIS SLIDES

Talks

  • 04/06/2026 Dyadisc 9, Saint-Valery-sur-Somme
  • 21/05/2026 Combinatorics on Words workshop, Janov nad Nisou
  • 18/02/2026 Team seminary of Open University, Milton Keynes
  • 16/02/2026 Team seminary of Queen Mary University of London
  • 06/11/2025 Team seminary, Prague
  • 14/10/2025 Séminaire Ernest, Marseille
  • 07/07/2025 Dyadisc 8, Amiens (invited speaker)
  • 16/06/2025 EJCIFM, Caen
  • 05/06/2025 Séminaire d'équipe, Liège
  • 29/05/2025 Combinatorics on Words workshop, Janov nad Nisou
  • 23/10/2024 Séminaire doctorants, Marseille
  • 06/09/2024 Journées Montoises d'informatique théorique, Nice
  • 02/07/2024 Groupe de travail Porkroll, Porquerolles
  • 27/06/2024 GASCOM, Bordeaux
  • 29/05/2024 Journées SDA2, Orléans
  • 27/03/2024 Séminaire doctorants, Marseille
  • 09/11/2023 Séminaire doctorants, Luminy

Teaching

Mathematics :

  • 2023-2024
    • Analyse (L1 Portail Descartes Aix)
    • Algèbre linéaire (L1 Portail Descartes Aix)
  • 2024-2025
    • Polynômes (L2 Maths)
  • 2025-2026
    • Polynômes (L2 Maths)

Computer Science :

  • 2024-2025
    • Programmation C (L2 info)
    • Fonctionnement des ordinateurs (L1 Portail Descartes)
  • 2025-2026
    • Programmation Python (L3 maths)