For each positive even integer j there is an infinite arithmetic seque
nce of dimensions d for which we construct a j-simplex of maximum volu
me in the d-dimensional unit cube. For fixed d, all of these maximal j
-simplices have the same Gram matrix, which is a multiple of I + J. Fo
r j even, a new upper bound for the volume of a j-simplex in the d-dim
ensional unit cube is given. (C) 1997 Academic Press.