共查询到20条相似文献,搜索用时 46 毫秒
1.
Given a unital associative commutative ring containing
, we consider a homotope of a Novikov algebra, i.e., an algebra
that is obtained from a Novikov algebra A by means of the derived operation
on the -module A, where the mapping satisfies the equality
. We find conditions for a homotope of a Novikov algebra to be again a Novikov algebra. 相似文献
2.
El-B. Yallaoui 《Periodica Mathematica Hungarica》1991,23(2):109-120
Let X be an abstract set and L a lattice of subsets of X. To each lattice regular measure µ, we associate two induced measures
and
on suitable lattices of the Wallman space IR(L) and another measure µ on the spaceIR(L). We will investigate the reflection of smoothness properties of p onto
,
and µ; and try to set some new criterion for repleteness and measure repleteness. 相似文献
3.
G. L. Booth 《Periodica Mathematica Hungarica》1991,22(3):175-182
The Brown-McCoy radical
is known to be an ideal-hereditary Kurosh-Amitsur radical in the variety of zerosymmetric near-rings. We define the Brown-McCoy and simplical radicals,
and
, respectively, for zerosymmetric -near-rings. Both
and
are ideal-hereditary Kurosh-Amitsur radicals in that variety. IfM is a zerosymmetric -near-ring with left operator near-ringL, it is shown that
, with equality ifM has a strong left unity.
is extended to the variety of arbitrary near-rings, and
and
are extended to the variety of arbitrary -near-rings, in a way that they remain Kurosh-Amitsur radicals. IfN is a near-ring andA N, then
, with equality ifA if left invariant. 相似文献
4.
LetS be a 0-distributive semilattice and
be its minimal spectrum. It is shown that
is Hausdorff. The compactness of
has been characterized in several ways. A representation theorem (like Stone's theorem for Boolean algebras) for disjunctive, 0-distributive semilattices is obtained. 相似文献
5.
Gerd Herzog 《Periodica Mathematica Hungarica》1995,30(3):205-210
Given a sequence (
n
)
n
in
with
there are functions
such that
, is a dense subset of
, and the set of functions with this property is residual in
. We will show that in
and some related Banach spaceX there are functionsf with
is dense in
, and we will give a sufficient condition when the set of such functions is residual inX. 相似文献
6.
Johannes Schoissengeier 《Monatshefte für Mathematik》1992,114(2):139-147
A proof of the formula
for locally compact fields
andC
1-isomorphisms :UV, whereU andV are open subsets of
, was never published. In this paper we give two short proofs, one of them is a more elementary variant of the other. 相似文献
7.
M. Wiessner 《Periodica Mathematica Hungarica》1993,26(3):205-210
Given
and a sequence of Dirichlet polynomials
estimates for the coefficientsa
n are proved if {n} is uniformly bounded on a region containing a half plane. Thereby a result is obtained which is an analogue of a known result for polynomials, that is for theA-transforms of the geometric sequence; moreover a Jentzsch type theorem for {n(z)} is derived. 相似文献
8.
A. Cossidente J. W. P. Hirschfeld G. Korchmáros F. Torres 《Compositio Mathematica》2000,121(2):163-181
The number N of rational points on an algebraic curve of genus g over a finite field
satisfies the Hasse–Weil bound
. A curve that attains this bound is called maximal. With
and
, it is known that maximalcurves have
. Maximal curves with
have been characterized up to isomorphism. A natural genus to be studied is
and for this genus there are two non-isomorphic maximal curves known when
. Here, a maximal curve with genus g
2 and a non-singular plane model is characterized as a Fermat curve of degree
. 相似文献
9.
Tamás Szönyi 《Graphs and Combinatorics》1991,7(3):279-287
A complete arc in a projective plane of orderq has at least
points. We show the existence of completek-arcs having
points in certain André planes of square order. Moreover our construction shows that for all
x > \sqrt q \log q$$
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there are completek-arcs withx < k < Cxlogq, for some absolute constantC. 相似文献
10.
Summary The existence of optimal nodes with preassigned multiplicities is proved for the Hardy spacesH
p
(1<p<). This is then used to show that the exact order of convergence for the optimal qudrature formula withN nodes (including multiplicity) is
where 1/p+1/q=1 and 1p. 相似文献
11.
Let
be the j-fold iterated function of
. Let
and > 0 be fixed, Q be a prime, and let N
k(Q|x) denote the number of those nx for which Q
. We give the asymptotics of N
k(Q|x) in the range
. 相似文献
12.
H. Fiedler 《Aequationes Mathematicae》1986,31(1):294-299
LetX={x
1,x
2,...,
n
}I=[–1, 1] and
. ForfC
1(I) definef* byf–p
f
=f*, wherep
f
denotes the interpolation-polynomial off with respect toX. We state some properties of the operatorf f*. In particular, we treat the case whereX consists of the zeros of the Chebyshev polynomialT
n
(x) and obtain x
m
–p
x
m8eE
n–1(x
m
), whereE
n–1(f) denotes the sup-norm distance fromf to the polynomials of degree less thann. Finally we state a lower estimate forE
n
(f) that omits theassumptionf
(n+1)>0 in a similar estimate of Meinardus. 相似文献
13.
Summary We investigate the asymptotic behaviour of
n
(n),n where
n
(x) denotes the Laguerre polynomial of degreen. Our results give a partial answer to the conjecture
n
(n)>1 forn>6, made in 1984 by van Iseghem. We also show the connection between this conjecture and the continued fraction approximants of
.Work sponsored by the Consiglio Nazionale delle Ricerche and by the Ministero dell'Università e della Ricerca Scientifica e Tecnologica of Italy 相似文献
14.
We prove four theorems about groups with a dihedral (or cyclic) image containing a difference set. For the first two, suppose G, a group of order 2p
with p an odd prime, contains a nontrivial (v, k, ) difference set D with order n = k – prime to p and self-conjugate modulo p. If G has an image of order p, then 0 2a +
2
for a unique choice of = ±1, and for a = (k –
)/2p. If G has an image of order 2p, then
and
(
– 1)/(
– 1). There are further constraints on n, a and . We give examples in which these theorems imply no difference set can exist in a group of a specified order, including filling in some entries in Smith's extension to nonabelian groups of Lander's tables. A similar theorem covers the case when p|n. Finally, we show that if G contains a nontrivial (v, k, ) difference set D and has a dihedral image D
2m
with either (n, m) = 1 or m = p
t
for p an odd prime dividing n, then one of the C
2 intersection numbers of D is divisible by m. Again, this gives some non-existence results. 相似文献
15.
Detlef Dürr Sheldon Goldstein Joel L. Lebowitz 《Probability Theory and Related Fields》1987,75(2):279-290
Summary We generalize the results of Spitzer, Jepsen and others [1–4] on the motion of a tagged particle in a uniform one dimensional system of point particles undergoing elastic collisions to the case where there is also an external potential U(x). When U(x) is periodic or random (bounded and statistically translation invariant) then the scaled trajectory of a tagged particle
converges, as A , to a Brownian motion W
D
(t) with diffusion constant
, where
is the average density,
is the mean absolute velocity and –1 the temperature of the system. When U(x) is itself changing on a macroscopic scale, i.e.
, then the limiting process is a spatially dependent diffusion. The stochastic differential equation describing this process is now non-linear, and is particularly simple in Stratonovich form. This lends weight to the belief that heuristics are best done in that form.Dedicated to Frank Spitzer on the occasion of his 60th birthdayWork supported in part by NSF Grants No. PHY 8201708 and No. DMR 81-14726Heisenberg-fellowAlso Department of Physics 相似文献
16.
Vladimír Müller 《Integral Equations and Operator Theory》1992,15(6):1033-1041
If belongs to the essential approximate point spectrum of a Banach space operatorTB(X) and
is a sequence of positive numbers with lim
j
a
j
=0, then there existsxX such that
for every polynomialp. This result is the best possible — if
for some constantc>0 thenT has already a non-trivial invariant subspace, which is not true in general. 相似文献
17.
The sequence of orthogonal polynomials
is said to be classical if
is also orthogonal. The aim of this paper is to find the sequences
which have the property that
is also orthogonal. We prove that sequences, with this property have to be, classical and belong either to the set of Laguerre or Jacobi polynomials, where in the Laguerre case c has to be zero and in the Jacobi case c = ±1. 相似文献
18.
Martin Bokler 《Designs, Codes and Cryptography》2001,24(2):131-144
In this paper minimal m-blocking sets of cardinality at most
in projective spaces PG(n,q) of square order q, q 16, are characterized to be (t, 2(m-t-1))-cones for some t with
. In particular we will find the smallest m-blocking sets that generate the whole space PG(n,q) for 2m n m. 相似文献
19.
In this paper geodesically corresponding metricsg and
on a manifoldM, dim 5, under the assumption that the tensorsR andS of the metricg satisfyR.R=Q(S, R), are considered. It is stated that the corresponding tensors
and
of
not necessarily must satisfy
. Certain relations between the curvatures ofg and
are obtained.Supported by a post-doctoral fellowship of the researchcouncil of the KU Leuven; Bitnet FGBDA3O at BLEKUL11 相似文献
20.
We prove that for every (infinite cardinal) there is a T
3-space X with clopen basis,
points such that every closed subspace of cardinality <
has cardinality < . 相似文献