COMMUNICATIONS IN ALGEBRA
Volume 27, Number 7, 1999
CONTENTS
Properness, Strictness, and Nilness in Jordan Systems . . . 3041 K. McCrimmon
Strict Proper Nilness Modulo an Absorber . . . 3067 K. McCrimmon
Henselian Valued Quasi-local Fields with Totally Indivisible
Value Groups . . . 3093 /. D. Chipchakov
Automorphism and Similarity Groups of Forms Determined by
the Characteristic Polynomial . . . 3109 A. Wesotowski
Kawamata-Viehweg Vanishing and Quint-Canonical Map of a
Complex T h r e e f o l d . . . 3117 M. Chen
On Derivations of Prime R i n g s . . . 3129 M. Bresar, M. A. Chebotar, and P. Semrl
Star Operations and Primitive Polynomials . . . 3137 D. D. Anderson and M. Zafrullah
On Finite Groups with Few Non-normal Subgroups . . . 3143 H. Mousavi
The Half-Factorial Property in Integral E x t e n s i o n s . . . 3153 J. Coykendall
On Radicals of a Left-Symmetric A l g e b r a . . . 3161 K. S. Chang, H. Kirn. and H. C. Myung
Complementation and Chief Factors. Ill . . . 3177 H. Bechtell
The Herzog-Vasconcelos Conjecture for Affine Semigroup Rings.... 3197 G. Muller and D. P. Patil
vii
viii CONTENTS Diagrams for Symplectic Type Configurations . . . 3201 H. Cardenas, E. Lluis, A. G. Raggi-Cdrdenas, and
R. San Agustin
Sur la Complexite du Calcul des Projections d'une Courbe
P r o j e c t i v e . . . 3211 /. Bermejo and M. Lejeune-Jalabert
Stability of Associated Primes and Equality of Ordinary and
Symbolic Powers of I d e a l s . . . 3221 S. Morey
The Centralizer Algebras of Lie Color Algebras... 3233 D. Moon
New Asymptotics for the Existence of Plane Curves with
Prescribed S i n g u l a r i t i e s . . . 3263 C. Lossen
Coinduction for Semigroup-Graded Rings . . . 3283 G. Abrams and C. Menini
Branching Rules for Two Row Partitions and Applications to the
Inductive Systems for Symmetric G r o u p s . . . 3303 J. Sheth
On the Regular Radical of a Group Ring . . . 3317 M. M. Parmenter and E. Spiegel
On the Determinant Class of an Algebra with Unitary Involution... 3329 A. Queguiner
Local Bijective Gabriel Correspondence and Relative Fully
Boundedness in -r-Noetherian Rings . . . 3339 P. Kirn and G. Krause
Group Actions in a Unit-Regular Ring... 3353 J.Han
Partial Character Degrees and Length of Soluble Groups: The
/^-Length 1 Case . . . 3363 M. Cazzola
Local Representation Theory and Mobius Inversion... 3377 L. Barker
On Algebras of Rank Three . . . 3401 S. Walcher
CONTENTS ix Spherical Orbits and Quantized Enveloping Algebras . . . 3439 N. Cantarini
A Free Resolution of a Binomial I d e a l . . . 3459 K.Eto
A Note on Generic Splitting of Quadratic Forms . . . 3473 R. Aravire and R. Baeza
On Pi-Algebras in Positive C h a r a c t e r i s t i c . . . 3479 D. Rumynin
On the Existence of Components of the Hilbert Scheme with the
Expected Number of Moduli. II . . . 3485 A. F. Lopez
Rings of Quotients of^-Rings by Gabriel Filters of I d e a l s . . . 3495 J. Martinez and W. W. McGovern
Vector Bundles on the Projective Line over a Discrete Valuation
Ring and the Cohomology of Canonical S h e a v e s . . . 3513 R. Hilbl and X. Sun
Certain Cyclically Presented Groups Are I s o m o r p h i c . . . 3531 D. L. Johnson, A. C. Kirn, and E. A. 0 'Brien
Injective Modules Graded by G-Sets ... 3537 D. Bulacu
Group Algebras and Enveloping Algebras with Nonmatrix and
Semigroup Identities... 3545 D. M. Riley and M. C. Wilson
Products of Idempotents of Defect 1 in Certain Semigroups of
Transformations... 3557 X. Yang
COMMUNICATIONS IN ALGEBRA Volume 27, Number 8,1999
CONTENTS
The Wedderburn-Malcev Theorem for Comodule Algebras . . . 3569 D. §tefan and F. Van Oystaeyen
Strongly Clean Rings and Fitting's Lemma . . . 3583 W. K. Nicholson
Vertex Operator Representations for Toroidal Lie Algebra of
Type B, . . . 3593 S. Tan
Groups with Exponent S i x . . . 3619 G. Havas, M. F. Newman, A. C. Niemeyer, and C. C. Sims
Non-cancellation for Certain Classes of Groups . . . 3639 P. J. Witbooi
On an Approximation Theorem for Krull Rings with Zero
D i v i s o r s . . . 3647 E. Osmanagic
The General Radical Theory of Incidence A l g e b r a s . . . 3659 S. Veldsman
A Link Between a Natural Centralizer and the Smallest Essential
Ideal in Structural Matrix R i n g s . . . 3675 L. Van Wyk
Generalized Twisted Group Rings of Finite G r o u p s . . . 3685 E. Nauwelaerts and F. Van Oystaeyen
The Albert Algebra of Generic Matrices... 3703 H. P. Petersson
Quadratic Forms for A-Good Module Categories of Quasi-
hereditary A l g e b r a s . . . 3719 S. Liu and C. Xi
Finite Two-Arc Transitive Graphs Admitting a Suzuki Simple
Group . . . 3727 X. G. Fang and C. E. Praeger
vii
viii CONTENTS Finite Two-Arc Transitive Graphs Admitting a Ree Simple Group.... 3755 X. G. Fang and C. E. Praeger
On the Density of Ratios ofChern Numbers of Embedded
Threefolds . . . 3771 M.-C. Chang
The Product of an Integrally Closed Ideal with Its Inverse . . . 3777 P. Constapel
Modules with Null Delta Invariants . . . 3781 Y. Yoshino
Richman Extensions of an Integral Domain . . . 3801 N. Onoda, T. Sugatani, and K. Yoshida
Universal Central Extension and the Second Invariant of
Homology of Crossed Modules in Lie A l g e b r a s . . . 3811 J. Af. Casas
Reduction Number One for Finitely Generated Torsion-Free
Modules . . . 3823 J.-C. Liu
Anneaux Noetheriens de H i l b e r t . . . 3833 A. Ayache andP.-J. Cahen
Central Internal Algebras and Varieties . . . 3851 A. V. Kelarev and T. Stokes
Semisimple Artinian Graded R i n g s . . . 3863 J. Cazaran and A. V. Kelarev
When Is the CS Condition H e r e d i t a r y ? . . . 3875 G. F. Birkenmeier, J. Y. Kirn, andJ. K. Park
A Going-Up Theorem for Arbitrary Chains of Prime I d e a l s . . . 3887 D. E. Dobbs
On the Rank of a Product of Two Finite p-Groups and Nilpotent
/^-Algebras . . . 3895 B. Amberg and L. S. Kazarin
Pfaffian Ideals of Linear Type . . . 3909 C. Baetica
Preinjective Modules and Finite Representation Type of Artinian
R i n g s . . . 3921 N. V. Dung
CONTENTS ix Asymptotic Prime Ideals Related to Exact Functors . . . 3949 K. Divaani-Aazar and M. Tousi
On Rings in Which Every Maximal One-Sided Ideal Contains a
Maximal I d e a l . . . 3969 K Lee and C. Huh
Verma Type Modules for Toroidal Lie A l g e b r a s . . . 3979 V. Futorny and I. Kashuba
Classification of Simple Space Curve S i n g u l a r i t i e s . . . 3993 A. Friihbis-Kruger
Geometrical Equivalence of G r o u p s . . . 4015 B. Plotkin, E. Plotkin. and A. Tsurkov
Injectivity of Functors to Modules and DGA's . . . 4027 M. Golasiriski
Invariance of Dimension of^-Subspaces in Bernstein Algebras . . . 4039 R. Costa and J. Picanqo
Generalized Derivations of Left Faithful R i n g s . . . 4057 T.-K. Lee
On Commutative Noetherian Rings Which Satisfy the Generalized
Radical F o r m u l a . . . 4075 S. H. Man
A Classification of Maximal Inverse Subsemigroups of the Finite
Symmetric Inverse Semigroups . . . 4089 X. Yang
Hodge Numbers of Nodal Double O c t i c s . . . 4097 S. Cynk
