Combinatorica, Volume 11

Volume 11, Number 1, 1991

K. T. Arasu, James A. Davis, Dieter Jungnickel, Alexander Pott: Some nonexistence results on divisible difference sets. 1-8
Endre Boros, Dieter Jungnickel, Scott A. Vanstone: The existence of non-trivial hyperfactorization of K_2n. 9-15
Jeff Kahn, Roy Meshulam: On mod p transversals. 17-22
Valerie King: An Omega(n^5/4) lower bound on the randomized complexity of graph properties. 23-32
Donald E. Knuth: Efficient representation of perm groups. 33-43
Tomasz Luczak: The chromatic number of random graphs. 45-54
Victor Neumann-Lara, Eduardo Rivera-Campo: Spanning trees with bounded degrees. 55-61
Noam Nisan: Pseudorandom bits for constant depth circuits. 63-70

Notes

Yoshimi Egawa, Atsushi Kaneko, Makoto Matsumoto: A mixed version of Menger's theorem. 71-74
Zoltán Füredi: On a Turán type problem of Erdös. 75-79

Robert E. L. Aldred, Derek A. Holton, Bill Jackson: Uniform cyclic edge connectivity in cubic graphs. 81-96
Noga Alon, Yossi Azar: Parallel comparison algorithms for approximation problems. 97-122
Roland Häggkvist, Andrew Thomason: Trees in tournaments. 123-130
Péter Hajnal: An Omega(n^4/3) lower bound on the randomized complexity of graph properties. 131-143
Nora Hartsfield, Gerhard Ringel: Clean triangulations. 145-155
Bala Kalyanasundaram, Georg Schnitger: On the power of white pebbles. 157-171
Xiaoyun Lu: On claws belonging to every tournament. 173-179

Note

András Gyárfás, Jenö Lehel: Effective on-line coloring of P₅-free graphs. 181-184

H. L. Abbott, Bing Zhou: The edge density of 4-critical planar graphs. 185-189
J. A. Bondy, Genghua Fan: Cycles in weighted graphs. 191-205
Charles J. Colbourn, Dean G. Hoffman, Kevin T. Phelps, Vojtech Rödl, Peter Winkler: The number of t-wise balance designs. 207-218
William H. Cunningham, Jan Green-Krótki: b-matching degree-sequence polyhedra. 219-230
Ervin Györi: On the number of edge disjoint cliques in graphs of given size. 231-243
Yoshiharu Kohayakawa: A note on induced cycles in Kneser graphs. 245-251
Hans Jürgen Prömel, Bernd Voigt: Graham-Rothschild parameter words and measurable partitions. 253-260
Paul D. Seymour: Directed circuits on a torus. 261-273
Bernd Sturmfels, Neil White: Computing combinatorial decompositions of rings. 275-293

Note

Tomasz Luczak: A note on the sharp concentration of the chromatic number of random graphs. 295-297

Béla Bollobás, Imre Leader: Edge-isoperimetric inequalities in the grid. 299-314
André Bouchet: An efficient algorithm to recognize locally equivalent graphs. 315-329
Joel Friedman: On the second eigenvalue and random walks n random d-regular graphs. 331-362
Jeff Kahn, Nathan Linial: Balancing extensions via Brunn-Minkowski. 363-368
Brendan D. McKay, Nicholas C. Wormald: Asymptotic enumeration by degree sequence of graphs with degress o(n^1/2). 369-382
Michael E. Saks, Michael Werman: On computing majority by comparisons. 383-387

Notes

Yoshimi Egawa, Akira Saito: Contractible edges in non-separating cycles. 389-392
Carsten Thomassen: Highly connected non-2-linked digraphs. 393-395