Volume 105, Number 1, January 2004
: Alternating groups An and 2-(v, k, 1) designs.
Ae Ja Yee
: Combinatorial proofs of Ramanujan's 11 summation and the q-Gauss summation.
V. M. Kharlamov
, S. Yu. Orevkov
: The number of trees half of whose vertices are leaves and asymptotic enumeration of plane real algebraic curves.
Volume 105, Number 2, February 2004
: Tiling the plane with congruent equilateral convex pentagons.
J. Robert Johnson
: Long cycles in the middle two layers of the discrete cube.
, Sergey Kitaev
: Crucial words and the complexity of some extremal problems for sets of prohibited words.