Opuscula Math. 35, no. 5 (2015), 665-688
http://dx.doi.org/10.7494/OpMath.2015.35.5.665

Opuscula Mathematica

# Katz's middle convolution and Yokoyama's extending operation

Toshio Oshima

Abstract. We give a concrete relation between Katz's middle convolution and Yokoyama's extension and show the equivalence of both algorithms using these operations for the reduction of Fuchsian systems on the Riemann sphere.

Keywords: Fuchsian systems, middle convolution.

Mathematics Subject Classification: 34M35, 34M40, 34M15.

Full text (pdf)

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• Toshio Oshima
• Josai University, Faculty of Science, 2-3-20, Hirakawacho, Chiyodaku, Tokyo 102-0093, Japan
• Communicated by P.A. Cojuhari.
• Revised: 2014-12-06.
• Accepted: 2015-01-17.
• Published online: 2015-04-27.