We give sufficient conditions for the naturallity of the exterior differential under Sobolev mappings. In other words we study the validity of the equation d f∗α = f∗ dα for a smooth form α and a Sobolev map f . The main results of the paper are Theorems 6.3 and 7.1. AMS Mathematics Subject Classification: 46E35, 58Dxx

We study the problem of holomorphic extension of a smooth CR mapping from a real analytic hypersurface to a real algebraic set in complex spaces of different dimensions. AMS Mathematics Subject Classification: 32D15,32D99,32F25,32H99

AMS Mathematics Subject Classification (2000): 26A33, 44A10

Let us denote by Zb(n) the number of trailing zeroes in the base b expansión of n!. In this paper we study with some detail the behavior of the function Zb. In particular, since Zb is non-decreasing, we will characterize the points where it increases and we will compute the amplitude of the jump in each of such points. In passing, we will study some asymptotic aspects and we will give families ...

AMS Mathematics Subject Classification (2000): 05C50

We prove that for every analytic curve in the complex plane C, Euclidean and spherical arc-lengths are global conformal parameters. We also prove that for any analytic curve in the hyperbolic plane, hyperbolic arc-length is also a global parameter. We generalize some of these results to the case of analytic curves in R and C and we discuss the situation of curves in the Riemann sphere C ∪ {∞}. ...

AMS Mathematics Subject Classification (2000): 65D30, 92E10

In this paper the Aumann and the Debreu integrals are introduced and results about their comparison are given in countably and finitely additive setting. 1991 AMS Mathematics Subject Classification: 28B20, 26E25, 46B20, 54C60

In this paper we approach the Compact Linear Operators Theory by the methods of Nonstandard Analysis. We present new proofs of several known results and some new results as well. AMS Mathematics Subject Classification (2000): 26E35, 47B07

The objective of the present paper is to study φ–recurrent Sasakian manifolds. AMS Mathematics Subject Classification (2000): 53C05, 53C20, 53C25