We give a survey of results on the Galois group of polynomials obtained by truncation of power series, the main example being the exponential series. We also present some evidence of a new phenomena: Galois groups of Padé approximation polynomials seem to have special properties as well.
Nous faisons un tour d’horizon de résultats sur les groupes de Galois de troncatures de séries entières, avec la série exponentielle comme figure de proue. On propose ensuite de nouvelles explorations avec des calculs explicites de groupes de Galois d’approximants de Padé qui semblent jouir, eux aussi, de propriétés intéressantes.
Revised:
Published online:
Mot clés : Groupes de Galois. Séries entières. Approximants de Padé
Keywords: Galois groups. Power series. Padé approximation
Patrick Rabarison 1; Fabien Pazuki 2, 3; Pascal Molin 4
@article{PMB_2024____105_0, author = {Patrick Rabarison and Fabien Pazuki and Pascal Molin}, title = {Exponentielle tronqu\'ee et autres contes galoisiens}, journal = {Publications math\'ematiques de Besan\c{c}on. Alg\`ebre et th\'eorie des nombres}, pages = {105--117}, publisher = {Presses universitaires de Franche-Comt\'e}, year = {2024}, doi = {10.5802/pmb.57}, language = {fr}, url = {https://pmb.centre-mersenne.org/articles/10.5802/pmb.57/} }
TY - JOUR AU - Patrick Rabarison AU - Fabien Pazuki AU - Pascal Molin TI - Exponentielle tronquée et autres contes galoisiens JO - Publications mathématiques de Besançon. Algèbre et théorie des nombres PY - 2024 SP - 105 EP - 117 PB - Presses universitaires de Franche-Comté UR - https://pmb.centre-mersenne.org/articles/10.5802/pmb.57/ DO - 10.5802/pmb.57 LA - fr ID - PMB_2024____105_0 ER -
%0 Journal Article %A Patrick Rabarison %A Fabien Pazuki %A Pascal Molin %T Exponentielle tronquée et autres contes galoisiens %J Publications mathématiques de Besançon. Algèbre et théorie des nombres %D 2024 %P 105-117 %I Presses universitaires de Franche-Comté %U https://pmb.centre-mersenne.org/articles/10.5802/pmb.57/ %R 10.5802/pmb.57 %G fr %F PMB_2024____105_0
Patrick Rabarison; Fabien Pazuki; Pascal Molin. Exponentielle tronquée et autres contes galoisiens. Publications mathématiques de Besançon. Algèbre et théorie des nombres (2024), pp. 105-117. doi : 10.5802/pmb.57. https://pmb.centre-mersenne.org/articles/10.5802/pmb.57/
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