l(f)=(-l)“(Pof’“‘)‘“‘+(-l)“-‘(p,f’”-”)’”~”+ ... +p,f=A.rf (0.1) on a finite or infinite interval (a, b) with real, locally summable coefficients l/PO,Pl, ..-3 Pnv r under the assumptions that p0 >O and that the weight function r changes its sign on (a, b). If r is positive, problem (0.1) can be studied in the context of Hermitian and self-adjoint operators in the Hilbert space L*(r) with the in...

We use the canonical Lipschitz geometry available on the boundary of a hyperbolic group to construct finitely summable Fredholm modules over the crossed product of the boundary action. The procedure yields a full set of representatives of the K-homology of the crossed product, and all of them are p-summable for p in an appropriate range related to the geometry of the boundary. By restricting th...

We present an algorithm which, given a hypergeometric term T (n), constructs hypergeometric terms T1(n) and T2(n) such that T (n) = T1(n + 1) ? T1(n) + T2(n), and T2(n) is minimal in some sense. This solves the decomposition problem for indeenite sums of hypergeometric terms: T1(n + 1) ? T1(n) is the \summable part" and T2(n) the \non-summable part" of T (n).

In this article we introduce and study the notions of double -lacunary strongly summable, double  Cesàro strongly summable, double  statistically convergent and double  -lacunary statistically convergent sequence of fuzzy numbers. Consequently we construct the spaces   2 F L  ,   2 F   ,   2 F S  and   2 F S  respectively and investigate the relationship among these spaces. F...

In this paper, we define the space Sαθ (∆mv, f) of all f)-lacunary statistical convergent sequences order α with help unbounded modulus function f, lacunary sequence (θ), generalized difference operator ∆ mv and real number ∈ (0, 1]. We also introduce ωαθ strong summable α. Properties related to these spaces are studied. Inclusion relations between ωα θ established under certain conditions.

Suppose G is an arbitrary additively written primary abelian group with a fixed large subgroup L. It is shown that G is (a) summable; (b) σ -summable; (c) a Σ-group; (d) pω+1-projective only when so is L. These claims extend results of such a kind obtained by Benabdallah, Eisenstadt, Irwin and Poluianov, Acta Math. Acad. Sci. Hungaricae (1970) and Khan, Proc. Indian Acad. Sci. Sect. A (1978).

Let D be a convex domain in C. Let ak > 0 be summable constants and let zk ∈ D. If the zk converge sufficiently rapidly to η ∈ ∂D from within an appropriate Stolz angle then the function ∑ ∞ k=1 ak/(z − zk) has infinitely many zeros in D. An example shows that the hypotheses on the zk are not redundant, and that two recently advanced conjectures are false. M.S.C. 2000 classification: 30D35, 31A...

We shortly illustrate how the field-theoretic approach to critical phenomena takes place in the more complete Wilson theory of renormalization and qualitatively discuss its domain of validity. By the way, we suggest that the differential renormalization functions (like the β-function) of the perturbative scalar theory in four dimensions (ϕ 4 4) should be Borel summable provided they are calcula...