Recall that we are now preparing the new 20th edition. Everybody is welcome to propose new problems to be included in the new edition. Problems may “belong” to those who propose them, or otherwise. In the latter case, one can indicate the author(s) of the problem (if different from the person proposing), or simply that this is a “well-known problem”. In order that the progress could be “measured” and seen, the preference is usually given to concrete questions that admit “yes” or “no” answers. New problems can be sent to any of the editors by e-mail: Evgeny Khukhro firstname.lastname@example.org or Victor Mazurov email@example.com . Later in the year we shall contact all the authors with “galley proofs” to make sure that the questions remain open and accurately stated (this also applies to several new problems that have already been received from various authors over the last years).
This 19th issue contains 111 new problems and a number of comments on about 1000 problems from the previous issues. The section “Archive of Solved Problems” includes all the solved problems from the previous issues that have already been commented on in previous issues, while new solutions are found among unsolved problems in the corresponding sections.