ANNOUNCEMENT OF CLOBBER PROBLEM COMPOSITION CONTEST
CLOBBER is a new combinatorial game invented last summer in
Halifax by Michael Albert, J. P. Grossman, and Richard Nowakowski.
The first competitive CLOBBER tournament was held at Dagstuhl, Germany,
in February 2002.
Clobber is played by two players, white and black, on a rectangular n x m
checkerboard. In the initial position, all squares are occupied by a
stone, with white stones on the white squares and black stones on the
black squares. A player moves by picking up one of their stones and
"clobbering" an opponent's stone on an adjacent square (horizontally or
vertically). The clobbered stone is removed from the board and replaced
by the stone that was moved. The game ends when one player, on their
turn, is unable to move, and then that player loses.
The game typically decomposes into many smaller positions. Values of
some of these positions have been cataloged at
Tools for further study of clobber and other games are available at
This note annoounces a $1,000 (Canadian) PRIZE FOR THE BEST
CLOBBER PROBLEM COMPOSITION(S).
At least one winner will be announced at the following meeting:
Third International Conference on Computers and Games
Edmonton, Canada, July 25-27 2002
If many outstanding problems are submitted,
there will be more than one prize. The winning problems and
their solutions are intended to be published, with commentary
by the judge(s).
A composed problem must specify a position and which player is to
move next. Each submission must also be accompanied by a solution
proposed by the composer. Although the solution might include
a modest number of computer-generated values, figures, or tables,
it must be intelligible to humans who have no access to
any machines. The solution should indicate how to play against
all plausible opposing strategies. Ideally, the proof that
the solution is correct should also require no machine assistance.
Difficult-yet-elegant problems which utilize combinatorial game
concepts such as atomic weights and/or thermography are especially
welcome. (e.g., See the Childish Hackenbush "Lollipops" problem
in Chapter 8 of Winning Ways.) It is very desirable (but not
required) that a problem have a history going back to the
conventional starting position. The board size must not exceed
10 x 10. Smaller board sizes are more desirable unless they entail
excessive compromises with the primary goals of difficulty and
Any entry, including solution, should not exceed three 8.5 x 11 inch
pages. To be eligible for a prize, an entry should be submitted by
and must be received before 11:59 pm, PDT, on July 20, 2002.