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1.
在Qp空间上建立了Jackson型不等式,即对任意f(z)=∑j=0 ^∞ αjz^j∈Qp,0≤p〈∞,α〉1及k-1∈N,有 ||f(z)-Г(k)/Г(k+α)∑ j=0 ^k-1Г(k-j+α)/Г(k-j)αjz^j||Qp≤C(α)ω(1/k,f,Qp),其中ω(1/k,f,Qp)为Qp空间中的连续模,C(α)是仅与参数α有关的正常数.  相似文献   

2.
A Jackson type inequality in Q p spaces is established, i.e., for any f (z) = Σ∞ j=0 ajzj ∈ Qp , 0≤p ∞, a 1, and k-1 ∈ N,where ω(1/k, f, Q p ) is the modulus of continuity in Q p spaces and C(a) is an absolute constant depending only on the parameter a.  相似文献   

3.
Let pj ∈ N and pj≥ 1, j = 2, ···, k, k ≥ 2 be a fixed positive integer. We introduce a Roper-Suffridge extension operator on the following Reinhardt domain ΩN ={z =(z1, z′2, ···, z′k)′∈ C × Cn2×···× Cnk: |z1|2+ ||z2||p22+ ··· + ||zk ||pk k 1} given11 by F P′j(zj),(f(z1))p2 z′2, ···,(f′(z1))pk z′k)′, where f is a normaljized biholomorphic function k(z) =(f(z1) + f′(z1)=2 on the unit disc D, and for 2 ≤ j ≤ k, Pj : Cnj-→ C is a homogeneous polynomial of degree pj and zj =(zj1, ···, zjnj)′∈ Cnj, nj ≥ 1, pj ≥ 1,nj1||zj ||j =()pj. In this paper, some conditions for Pjare found under which the loperator p |zjl|pj=1reserves the properties of almost starlikeness of order α, starlikeness of order αand strongly starlikeness of order α on ΩN, respectively.  相似文献   

4.
In this paper, we investigate the growth of solutions of the differential equations f~((k))+ A_(k-1)(z)f~((k-1))+ ··· + A_0(z)f = 0, where A_j(z)(j = 0, ···, k-1) are entire functions.When there exists some coefficient A_s(z)(s ∈ {1, ···, k-1}) being a nonzero solution of f'+P(z)f = 0, where P(z) is a polynomial with degree n(≥ 1) and A_0(z) satisfies σ(A_0) ≤1/2 or its Taylor expansion is Fabry gap, we obtain that every nonzero solution of such equations is of infinite order.  相似文献   

5.
Let f be a holomorphic function on the unit polydisc Dn,with Taylor expansion f(z) = ∞ |k|=0 akzk ≡∞ (k1+···+kn=0) (ak1,···,kn zk1 1znkn)where k = (k1, , kn) ∈ Z+n. The authors define generalized Hilbert operator on Dn by Hγ,n(f)(z) = ∞ |k|=0 i1,···,in≥0 ai1,···,in n j=1 Γ(γj + kj + 1)Γ(kj + ij + 1) Γ(kj + 1)Γ(kj + ij + γj + 2) zk,where γ∈ Cn, such that R γj > -1, j = 1, 2, , n. An upper bound for the norm of the operator on Hardy spaces Hp(Dn) is found. The authors also present a Fejér-Riesz type inequalit...  相似文献   

6.
该文研究了一类高阶整函数系数微分方程解的增长性,对方程f~(k)+A_(k-1)(z)e~(ak-1z).f~(k-1)+…+A_0(z)e~(a0z)f=0与方程f~(k)+(A_(k-1)(z)e~(ak-1z)+D_(k-1)(z))f~(k-1)+…+(A_0(z)e~(a0z)+D_0(z))f=0中a_j(0≤j≤k-1)幅角主值不全相等的情形,得到了解的增长级、下级与超级的精确估计.  相似文献   

7.
本文研究了在Aj(z),aj(j=0,1,…,k-1)满足一些条件下方程f(k)+Ak-1(z)eak-1f(k-1)+…+A0(z)ea0zf=0解的超级和在Aj(z),Pj(j)(j=0,1,…,k-1)满足一些条件下方程f(k)+Ak-1(z)ePk-1(z)f(k-1)+…+Aj(z)eajzf(j)+…+A0(z)eP0(z)f=0解的级。  相似文献   

8.
江海新  吴芸 《数学学报》2013,(1):135-144
讨论了ω,q-Bernstein多项式的Voronovskaya-型公式及其收敛的饱和性.给出了当01[0,1]时ω,q-Bernstein多项式的Voronovskaya-型公式.如果0<ω,q<1,f∈C1[0,1]时ω,q-Bernstein多项式的Voronovskaya-型公式.如果0<ω,q<1,f∈C1[0,1],则ω,q-Bernstein多项式的收敛阶为o(q1[0,1],则ω,q-Bernstein多项式的收敛阶为o(qn)当且仅当((f(1-qn)当且仅当((f(1-q(k-1)-f(1-q)(k-1)-f(1-q)k))/((1-qk))/((1-q(k-1)-(1-q(k-1)-(1-qk)))=f'(1-qk)))=f'(1-qk),k=1,2,…还证明f如果f在[0,1]是凸的或者在(-ε,1+ε)(ε>0)解析,则ω,q-Bernstein多项式的收敛阶为o(qk),k=1,2,…还证明f如果f在[0,1]是凸的或者在(-ε,1+ε)(ε>0)解析,则ω,q-Bernstein多项式的收敛阶为o(qn)当且仅当f是线性函数.  相似文献   

9.
Let ∫ be a holomorphic function on the unit polydisc Dn, with Taylor expansion ∫(z)= ∞∑|k|=0αkzk(=)∞∑k1+…+kn=0 αk1, …,knZk11…Zknn where k=(k1,…, kn)∈Zn+. The authors define generalized Hilbert operator on Dn by Hγ,n(f)(z)=∞ ∑|k|=0i1,…in≥0αi1,…,inn∏j=1Γ(γj+kj+1) Γ(kj+ij+1)/Γ(kj+1) Γ(kj+ij+γj+2)zk,where γ∈Cn, such that Rγj -1,j = 1,2,…,n. An upper bound for the norm of the operator on Hardy spaces Hp(Dn) is found. The authors also present a Fejér-Riesz type inequality on the weighted Bergman space on Dn and find an invariant space for the generalized Hilbert operator.  相似文献   

10.
研究了解析函数与Lipschitz条件,得到了如下两个结果:(i)设D是一平面区域,f(z)在D中解析,00,对任意z∈D有|f′(z)|≤md(z,D)k-1,则f∈Lipk(D)且‖f‖k≤cmk,其中c=c(D)是仅与D有关的常数.  相似文献   

11.
Let H(D)be the collection of functions which are analytic in the unitdisc D.we call B_0={f∈H(D),(?)(1-|z|~2)|f’(z)|=0}litlle Bloch space.Letf∈H(D),0相似文献   

12.
将Stein[On the functions of Littlewood-Paley,Lusin,and Marcinkiewicz,Trans.Amer.Math.Soc.,1958,88:430-466]中的玛欣凯维奇函数的逆向不等式推广到一般情形.主要结果是对于n-维欧几里得空间k-阶球面调和函数空间的任意一基底,得到玛欣凯维奇函数的一般性的逆向不等式,即存在不依赖于函数f正常数C_p,使得||f||_p≤C_pΣ_(j=1)~N=1||μ_j(f)||_p,其中{μ_j(f)}_(j=1)~N是f的由这些球面调和函数生成的玛欣凯维奇函数.此外,对于任意的n-变元的k-阶调和多项式Q(x)以及泊松核P_t(x),有Q(D)P_t(x)=C_n k(tQ(x))/((|x|)~2+t~2~(n+2k+1)/2).  相似文献   

13.
研究了一类线性非齐次微分方程f(k)+ak-1f(k-1)+…+a1f-′(eQ(z)-a0)f=eQ(z)+F(z)解的增长性,其中aj(j=0,1,…,k-1)为常数,Q(z)为非常数多项式,F(z)为级小于deg Q的整函数.  相似文献   

14.
We determine all real meromorphic functions f in the plane such that f has finitely many zeros, the poles of f have bounded multiplicities, and f and F have finitely many non-real zeros, where F is a linear differential polynomial given by F = f (k) +Σk-1j=0ajf(j) , in which k≥2 and the coefficients aj are real numbers with a0≠0.  相似文献   

15.
《数学季刊》2016,(4):369-378
In this paper, we investigate the growth of solutions of the differential equations f(k)+Ak?1(z)f(k?1)+· · ·+A0(z)f =0, where Aj(z)(j=0, · · · , k?1) are entire functions. When there exists some coe?cient As(z)(s ∈ {1, · · · , k?1}) being a nonzero solution of f00+P(z)f =0, where P(z) is a polynomial with degree n(≥1) and A0(z) satisfiesσ(A0)≤1/2 or its Taylor expansion is Fabry gap, we obtain that every nonzero solution of such equations is of infinite order.  相似文献   

16.
本文研究了微分方程f(k) (Ak-1(z)eak-1z Dk-1(z))f(k-1) … (A0(z)ea0z D0(z))f=0解的增长性问题,针对方程中aj(0≤j≤k-1)的幅角主值不全相等的情形,得到了方程解的增长级和超级的精确估计.  相似文献   

17.
Define the differential operators ?_n for n∈N inductively by ?_1 [f](z)=f(z) and ?_(n+1) [f](z)=f(z)?_n[f](z)+d/dz ?_n[f](z).For a positive integer k≥2 and a positive number δ,let F be the family of functions f meromorphic on domain D■C such that ?_k[f](z)≠0 and |Res(f,a)-j|≥δ for all j∈{0,1,…,k-1} and all simple poles a of f in D.Then F is quasi-normal on D of order 1.  相似文献   

18.
Let G(V, E) be a graph. A k-adjacent vertex-distinguishing equatable edge coloring of G, k-AVEEC for short, is a proper edge coloring f if (1) C(u)≠C(v) for uv ∈ E(G), where C(u) = {f(uv)|uv ∈ E}, and (2) for any i, j = 1, 2,… k, we have ||Ei| |Ej|| ≤ 1, where Ei = {e|e ∈ E(G) and f(e) = i}. χáve (G) = min{k| there exists a k-AVEEC of G} is called the adjacent vertex-distinguishing equitable edge chromatic number of G. In this paper, we obtain the χáve (G) of some special graphs and present a conjecture.  相似文献   

19.
The generalized Roper-Suffridge extension operator Ф(f) on the bounded complete Reinhardt domain Ω in Cn with n ≥ 2 is defined by Φrn,β2,γ2,…,βn,γn(f)(z)=(rf(z1/r),(rf(z1/r)/z1)β2(f'(z1/r))γ2z2,…,(rf(z1/r)/z1)βn(f'(z1/r)γnzn) for (z1,z2,…,zn) ∈Ω, where r = r(Ω) = sup{|z1| (z1,z2,…,zn) ∈ Ω},0 ≤ γj ≤ 1 -βj,0 ≤ βj ≤ 1,and we choose the branch of the power functions such that (f(z1)/z1)βj |z1=0 = 1 and (f′(z1))γj |z1=0 =1,j = 2,…,n. In this paper, we prove that the operator Фrn,β2,γ2,…,βn,γn(f) is from the subset of S*α(U) to S*α(Ω)(0 ≤ α < 1) on Ω and the operator Фrn,β2,γ2,…, βn,γn(f) preserves the starlikeness of order α or the spirallikeness of type β on Dp for some suitable constantsβj,γj,pj, where Dp ={(z1,z2,…,zn) ∈ Cn ∑nj=1|zj|pj < 1} (pj > 0, j = 1,2,…,n), U is the unit disc in the complex plane C, and Sα* (Ω) is the class of all normalized starlike mappings of order α on Ω. We also obtain that Φrn,β2,γ2,…,γn(f) ∈ S*α(Dp) if and only if f ∈ S*a(U) for 0 ≤ α < 1 and some suitable constants βj,γj,pj.  相似文献   

20.
本文利用不完全Kloosterman和的估计来研究短区间的并集中Woods问题的一个推广,并且给出了渐近公式.具体来讲,设p是奇素数,1≤H≤p,实数δ满足0δ≤1,并设I~((j))(1≤j≤J)是(0,p)的互不相交的子区间,满足H/2≤|I(j)|≤H.定义I=U_(j=1)~JI~((j)),以及A(δ,p)={a∈Z:1≤a,a瓦≤p-1,|a-a|δp},其中瓦是a关于模p的乘法逆,满足aa≡1(mod p).设x是模p的Dirichlet非主特征.本文证明了Σx∈Ix∈A(δ,p)1=1/p∫_0~(|δ,p|)((Σx∈Ix≤p-1-t)1+(Σx∈Ix≥t+1)1)dt+O(J~(1/2)P~(1/2)logHlog~2p),以及Σx∈Ix∈A(δ,p)X(x)《J~(1/2)P~(1/2)logHlog~2p.  相似文献   

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