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2.
( X
k
), k=1,2,... —
k
2
>1; ( X
k
) , E(X
k
X
t
)=0 p
k<>( p+1)
( p,k,l=1, 2, ...) , , ,
相似文献
3.
Let d be a finite positive Borel measure on the interval [0, 2] such that >0 almost everywhere; and W
n be a sequence of polynomials, deg W
n
= n, whose zeros ( w
n
,1,, w
n,n
lie in [| z|1]. Let d
n
<> for each nN, where d
n
= d/| W
n
( e
i
)| 2. We consider the table of polynomials
n,m such that for each fixed nN the system
n,m, mN, is orthonormal with respect to d
n
. If
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4.
A=( a
ij)
i
j=1
— k-o , a
ij
. :
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5.
We are concerned with the semilinear polyharmonic model problem (–) K v = v + v| v|
s–1 in B, D
v| B = 0 for ¦|<- K – 1. Here K , B is the unit ball in n, n >2K,
is the critical Sobolev exponent. Let 1 denote the first Dirichlet eigenvalue of (- ) K in B. The existence of a positive radial solution v is shown for
相似文献
7.
Let á A, B | Am=1, Bn= At, BAB-1= Ar?\langle A, B\,\vert\, A^\mu=1,\, B^\nu=A^t,\, BAB^{-1}=A^\rho\rangle
where and are relative prime numbers, t = / s and s = gcd( – 1,), and is the order of modulo . We prove that if (1) = 2, and (2) is embeddable into the multiplicative group of some skew field, then is circular. This means that there is some additive group N on which acts fixed point freely, and |(( a)+ b)(( c)+ d)| 2 whenever a,b,c,d N, a0 c, are such that ( a)+ b( c)+ d. 相似文献
8.
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9.
Let be a finite regular incidence-polytope. A realization of is given by an image V of its vertices under a mapping into some euclidean space, which is such that every element of the automorphism group () of induces an isometry of V. It is shown in this paper that the family of all possible realizations (up to congruence) of forms, in a natural way, a closed convex cone, which is also denoted by The dimension r of is the number of equivalence classes under () of diagonals of , and is also the number of unions of double cosets ** *–1* ( *), where * is the subgroup of () which fixes some given vertex of . The fine structure of corresponds to the irreducible orthogonal representations of (). If G is such a representation, let its degree be d
G
, and let the subgroup of G corresponding to * have a fixed space of dimension w
G
. Then the relations
相似文献
10.
, ( fz) , ,
相似文献
11.
m N k= m–2, m–1
相似文献
12.
. 0 pq, 1–1/ p+1/ p0. f( x) — n, [–1,1],
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15.
The positive half A
+ of an ordered abelian group A is the set { x Ax 0} and M
A
+ is a module if for all x, y M also x + y, |x – y| M. If A
+
\M then M() is the module generated by M and . S
M is unbounded in M if (x M)( y S)(x y) and is dense in M if (x 1, x 2 M)(y S) (x 1 <> 2 x 1 y x 2). If M is a module, or a subgroup of any abelian group, a real-valued g: M R is subadditive if g(x + y) g(x) + g(y) for all x, y M. The following hold: (1) |
IfM andM
* are modules inA andM
M
*
A
+ then a subadditiveg:M R can always be extended to a subadditive functionF:M
*
R when card(M) = 0 and card(M
*
) 1, or wheneverM
* possesses a countable dense subset.
| (2) |
IfZ
A is a subgroup (whereZ denotes the integers) andg:Z
+
R is subadditive with
g(n)/n = – theng cannot be subadditively extended toA
+ whenA does not contain an unbounded subset of cardinality
.
| (3) |
Assuming the Continuum Hypothesis, there is an ordered abelian groupA of cardinality 1 with a moduleM and elementA
+
/M for whichA
+
= M(), and a subadditiveg:M R which does not extend toA
+. This even happens withg 0.
| (4) |
Letg:A
+
R be subadditive on the positive halfA
+ ofA. Then the necessary and sufficient condition forg to admit a subadditive extension to the whole groupA is: sup{g(x + y) – g(x)x –y} < +="> for eachy <> inA.
| (5) |
IfM is a subgroup of any abelian groupA andg:M K is subadditive, whereK is an ordered abelian group, theng admits a subadditive extensionF:A K.
| (6) |
IfA is any abelian group andg:A R is subadditive, theng = + where:A R is additive and 0 is a non-negative subadditive function:A R. IfA is aQ-vector space may be takenQ-linear.
| (7) |
Ifg:V R is a continuous subadditive function on the real topological linear spaceV then there exists a continuous linear functional:V R and a continuous subadditive:V R such thatg = + and 0. ifV = R
n
this holds for measurable subadditiveg with a continuous and measurable.
| 相似文献
16.
We obtain upper and lower bounds for Christoffel functions for Freud weights by relatively new methods, including a new way to estimate discretization of potentials. We then deduce bounds for orthogonal polynomials on thereby largely resolving a 1976 conjecture of P. Nevai. For example, let W:= e
–Q, where Q: is even and continuous in, Q " is continuous in (0, ) and Q
'>0 in (0, ), while, for some A, B,
相似文献
18.
Let C be a simply connected domain, 0, and let n, nN, be the set of all polynomials of degree at most n. By n() we denote the subset of polynomials p n with p(0)=0 and p( D), where D stands for the unit disk { z: | z|<1}, and=" by=">1},>we denote the maximal range of these polynomials. Let f be a conformal mapping from D onto , f(0)=0. The main theme of this note is to relate n (or some important aspects of it) to the images f
s
( D), where f
s
(z):=f[(1–s)z], 0 s<1. for=" instance=" we=" prove=" the=" existence=" of=" a=" universal=">1.> c
0 such that, for n2 c
0, 相似文献
19.
,
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20.
The aim of this paper is to present relations between Goldie, hollow and Kurosh-Ore dimensions of semimodular lattices. Relations between Goldie and Kurosh-Ore dimensions of modular lattices were studied by Grzeszczuk, Okiski and Puczyowski. 相似文献
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