The Soma cube is a solid dissection puzzle invented by Piet Hein during a lecture on Quantum Mechanics by Werner Heisenberg. There are
seven soma pieces composed of all the irregular face-joined cubes (polycubes)
with cubes. The object is to assemble
the pieces into a cube. There are 240 essentially distinct
ways of doing so (Beeler 1972, Berlekamp et al. 1982), as first enumerated
one rainy afternoon in 1961 by J. H. Conway and Mike Guy.
Counting rotations and reflections of the whole cube separately gives arrangements. The larger count additionally distinguishes
orientations related by the rotational symmetries of
the individual pieces (Delahaye 2009, pp. 82-83). These counting conventions
do not depend on the colors assigned to the pieces.
cubes. The object is to assemble
the pieces into a cube. There are 240 essentially distinct
ways of doing so (Beeler 1972, Berlekamp et al. 1982), as first enumerated
one rainy afternoon in 1961 by J. H. Conway and Mike Guy.
arrangements. The larger count 
additionally distinguishes
orientations related by the rotational symmetries of
the individual pieces (Delahaye 2009, pp. 82-83). These counting conventions
do not depend on the colors assigned to the pieces.
