My opinion: A result computed by a computer algebra system, whose source code is not “open source”, can not be accepted as part of a mathematical proof. Within the general mathematical community, it seems fair to say that a mathematical truth is…

Lesson 1 by Igor Epshteyn. Theme: Introduction to pawn endgames: pawn mobility, opposition, triangulation. Lesson 2 by Igor Epshteyn. Theme: The principle of two weaknesses and the triangulation manuever. Lesson 3 by Igor Epshteyn. Theme: Coordinating squares, static case. The principle of…

Noam Elkies Editor’s note: This issue we introduce a new column to Chess Horizons readers. Mathematician, musician and chessmaster Noam Elkies is a member of Harvard University’s Society of Fellows and an internationally known endgame composer whose works have received numerous awards….

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