The problem was composed after I have found that the mating position is unique, so all different mates are automatically echoes. There was a long semi-manual search if it is possible to have four mates from different squares. This position was found during this search. “Semi-manual” means computer check of some family of positions. There were several perspective families of positions one of which (Qf2 and two queens on big diagonals) have allowed to find this position.
After I had found that four mates from all available mating squares are possible, I have run an exhaustive computer search. There are in fact 5 positions with four mates from different squares (short of rotation/reflection) in two families (example of second family: Qc7e5f4 – Kb1). From all 5 positions I prefer this one (repetition of some moves is always unavoidable). (Author)
I like this kind of puzzle with two parts… The first part is constructive task, where one has to look for the only possible mating position (it would be challenging even without the author’s hint). The second part is like more ordinary solving…
Jacques Rotenberg
December 20, 2017 14:14
In the solving process, for me, to find the mate net was rather difficult. Then to find the solutions was much easier.
The explanations of the author (that I read after solving) about the composing process are clear and interesting.
I like this kind of puzzle with two parts… The first part is constructive task, where one has to look for the only possible mating position (it would be challenging even without the author’s hint). The second part is like more ordinary solving…
In the solving process, for me, to find the mate net was rather difficult. Then to find the solutions was much easier.
The explanations of the author (that I read after solving) about the composing process are clear and interesting.
All in all a very nice problem to solve.