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An associative locally finite algebra which is also an integral domain over an algebraically closed field is isomorphic to the ground field.

We give a simplified proof to the following theorem due to D. Quillen: if A is a commutative noetherian ring of global dimension ⩽ 1 \leqslant 1 , then finitely generated projective modules over A [ T 1 , … , T n ] A[{T_1}, \ldots ,{T_n}] are extended from A. We prove also that if A is a commutative noetherian ring of global dimension d, then finitely generated projective modules of rank > d > d over A [ T 1 , … , T n ] A[{T_1}, \ldots ,{T_n}] are extended from A.

in subring of R and thus by hypothesis there exists a right identity for S, say e, = ~ a~ x~. i=1 Then xes=x, and if we set P~(t)= ~a~t ~-1 we have x2P~(x)=x. i=1 For each associator d=(u, v, w)ER there exists a polynomial Pe(t) such that d=d2Pa(d) and Slater's theorem implies that R is associative. At this point we could apply the result of Fuchs and Szele to finish; however we take a somewhat different route by next applying Herstein's theorem to see that R is commutative. Any ideal of R is of the form Re for some idempotent e, since it has an identity as a subring. Thus if 1 is the identity of R, R=Re| --e) and R is completely reducible and hence a finite direct sum of fields F 1 .... , F,. No F~ is of characteristic

In this short paper, generally, we define a family of functions fk depends on the Eisenstein series with weight 2k, for k ( N. More detail, by considering the function fk, we define a derivative formula for generating weakly modular forms with weight 12. As a result for this, we claim that this formula gives an advantage to find the special solutions of some differential equations.

Let I be the Stanley–Reisner ideal of a simplicial complex Δ. In this short paper, we shall give a formula of vanishing of the local cohomology modules for S/I(r) in the case Δ is a union of disjoint matroids, where I(r) is the rth symbolic power of I. As an application, we will improve a previous result in Minh and Nakamura (Nagoya Math. J. 213, 127–140, 2014) for the k-Buchsbaumness of S/I(r).

near a point solution xi ai (i 1, 1 *, n) when certain conditions are satisfied. In the present paper these conditions are replaced by less stringent ones; the methods of proof of certain existence theorems are very similar to those employed in the first paper, and these proofs are given here in an abbreviated forin. In addition, the asymptotic properties of certain trajectories are discussed by an extension of the methods of Bohl. On account of the more complicated form of certain quadratic forms which occur here, it has been convenient to leave undetermined certain constants which are determined explicitly in the first paper; this procedure, together with the algebraic method of transforming the canonical equations, reduces to a small amount the results common to both papers.

It has been brought to my attention by Mr. N. E. Steenrod that the lemma of page 708 in the paper referred to is in error. The final assertion of the proof is false. It is therefore necessary to point out that the paper is not "disturbed" by this fault. For if one requires that the Pn, «= 1,2, • • •, of the lemma be arcs then the (altered) lemma does hold, since it is true that the connected sum of a perfect continuous curve and an arc is "perfect." One verifies that this restricted lemma is sufficient for the uses of the paper.

J. L. Palacios claimed [2] that the author’s paper [1] contained errors. This note refutes those claims by showing that Palacios misunderstood [1] and adopted assumptions different from those of [1].

(1988). An Algebraic Approach to Some Number-Theoretic Problems Arising from Paper-Folding Regular Polygons. The American Mathematical Monthly: Vol. 95, No. 4, pp. 289-307.

There is a mistake in each of [3] and [4]. The purpose of this note is to correct the error in [3] and to salvage what can be saved in [4]. In each case the notation will be that of the paper under discussion. Professor Homer Bechtell has kindly informed me of an error in the proof of the Theorem of [3] which occurs in the case MG1c G. The theorem is true however by altering the proof at this point. Assume that Mc: MG1=M1lc:G. M1 is an invariant subgroup of G, and since G1c: Soc(G), G1 is a direct sum of minimal invariant subgroups of G. By Clifford's theorem (p. 70 of [1]), each minimal invariant subgroup of G is either M1-central or M1-hypereccentric, and hence

The first part of the theorem of the above paper states that if ois a closed convex set in real X1 ... Xn-space which is invariant under permutations of coordinates, and if C(o-) denotes the set of real symmetric nXn matrices whose eigenvalues X1, X. form the coordinates of points in a, then C(o) is convex. I am obliged to Professor R. T. Rockafellar for pointing out that this statement is essentially contained in a theorem of Chandler Davis.2 The statement also follows from an earlier result of V. B. Lidskii,3 which was not known to me at the time of publication.