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Those made of sterner stuff, however, will appreciate Ron Graham and Fan
Chung’s Erdös on Graphs, a beautifully produced collection of many of the
outstanding puzzles in graph theory left unsolved after Erdös’s death. And
there’s more than kudos awaiting those who solve some of the problems within,
too. Following one of Erdös’s typically eccentric traditions, the authors
are offering cash prizes of up to a thousand dollars to those who can solve
problems that even a benzedrine-powered genius couldn’t get his head round.
Published by A. K. Peters, £20/$30, ISBN 1568810792.