Lars Edvard Phragmén

Lars Edvard Phragmén (2 September 1863 Örebro – 13 March 1937) was a Swedish mathematician.

A first version was proposed by Phragmén, then improved by the Finnish mathematician Ernst Lindelöf.

He is also famous for having pointed out (at 26) an unclear part of Henri Poincaré's preprint on the three-body problem.

This led Poincaré to discover a major mistake in his own work, paving the way to important developments in chaos theory.

In addition to analysis, Phragmén was interested in the mathematics underlying insurance companies, and voting.