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1.
    
The algebra of all matrices over a field has a natural -grading . In this paper graded identities of the -graded algebra over a field of characteristic zero are studied. It is shown that all the -graded polynomial identities of follow from the following:

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2.
We show that all the zeros of the Fourier transforms of the functions , , are real and simple. Then, using this result, we show that there are infinitely many polynomials such that for each the translates of the function

generate . Finally, we discuss the problem of finding the minimum number of monomials , , which have the property that the translates of the functions , , generate , for a given .

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3.
Fix a positive integer and . We provide expressions for the weighted distance

where is normalized Lebesgue measure on the unit circle, is a nonnegative integrable function, and ranges over the trigonometric polynomials with frequencies in

or

These distances are related to other extremal problems, and are shown to be positive if and only if is integrable. In some cases they are expressed in terms of the series coefficients of the outer functions associated with .

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4.
We consider the Hausdorff measures , , defined on with the topology induced by the metric

for all . We study its properties, their relation to the ``Lebesgue measure" defined on by R. Baker in 1991, and the associated Hausdorff dimension. Finally, we give some examples.

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5.
In this paper, we prove the following general result. Let be a real Hilbert space and a continuously Gâteaux differentiable, nonconstant functional, with compact derivative, such that


Then, for each for which the set is not convex and for each convex set dense in , there exist and 0$"> such that the equation


has at least three solutions.

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6.
Let and be the eigenvalues of the matrix . The main result of the Method of Freezing states that if , and , then

for the highest exponent of the system, where

The previous best known value and the substantially smaller values of are reduced to the still smaller value.

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7.
We show that every positive solution of the equation

where , converges to a period two solution.

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8.
The Bochner-Riesz operator on of order is defined by

where denotes the Fourier transform and if , and if . We determine all pairs such that on of negative order is bounded from to . To be more precise, we prove that for the estimate holds if and only if , where

We also obtain some weak-type results for .

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9.
An open problem posed by G. Ladas is to investigate the difference equation


where are any nonnegative real numbers with 0$">. We prove that there exists a positive integer such that every positive solution of this equation is eventually periodic of period .

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10.
Let be a -semigroup with generator on a Banach space . Let be a fixed element. We prove the following individual stability results.

(i) Suppose is an ordered Banach space with weakly normal closed cone and assume there exists such that for all . If the local resolvent admits a bounded analytic extension to the right half-plane 0\}$">, then for all and we have


(ii) Suppose is a rearrangement invariant Banach function space over with order continuous norm. If is an element such that defines an element of , then for all and we have


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