In this paper we extend the results of an earlier note [1].

Definition. Let E be an extension field of the rationals. A vector v = (b1, …, bn) in En is algebraic if each coordinate bi is algebraic over the rationals. A linear transformation T: En → En is algebraic if T(v) is an algebraic vector for every algebraic vector v.

Definition. The degree of an algebraic linear transformation T, denoted by deg T, is the minimum of [K:Q] taken over all finite algebraic extensions K of the rationals Q such that T: Kn → Kn.

We define, as in [2], a random knock-out tournament with n players as a vector (m1, m2, …, mk) of positive integers satisfying

1

On the first round of the tournament 2m1 players, chosen at random, are paired off randomly; the remaining n — 2m1 players have a "bye". The m1 losers are knocked out, leaving a tournament n—m1 players with vector (m2, m3, …, mk).

Let R be a ring and G a group. The group ring RG consists of all functions f: G → R with finite support. Addition is pointwise and multiplication is defined for f, h ∊ RG and g ∊ G, by

The support group of f is defined to be the subgroup of G generated by the support of f. The element f is idempotent if ff = f

We prove the following result.

In his classic memoir on the moment problem that bears his name, Stieltjes [2] exhibited

1

as an example of an indeterminate (Stieltjes) moment sequence.

Stieltjes also obtained the corresponding S-fraction and thus implicitly obtained the three-term recurrence formula satisfied by the corresponding orthogonal polynomials.

Much current research is concerned with the fixed points of contractive mappings (mappings which shrink distance in some manner) from a metric space into itself. In this remark we shall point out that most mappings treated in the literature are very special in the sense that all these mappings satisfy a condition which is rather severe: every periodic point must necessarily be a fixed point.

It is well known that if A is an n × n complex matrix and AT is its transpose, then there is an invertible n x n complex matrix S such that AT = S-1AS. In this note we wish to point out another simple relation between A and AT.

If A is an n × n complex matrix and AT is its transpose then there are unitary n × n complex matrices U and V such that AT = UAV.

For any two integers n and k we take, as usual,

Using the above symbol we define a new function F(q, 2n) by a sum of two finite sums given by

1.1

for i ≠ q, and whenever q is an odd integer.

A (meet-) semilattice is an algebra with one binary operation ∧, which is associative, commutative and idempotent. Throughout this paper we are working in the category of semilattices. All categorical or general algebraic notions are to be understood in this category. In every semilattice S the relation

defines a partial ordering of S. The symbol "∨" denotes least upper bounds under this partial ordering. If it is not clear from the context in which partially ordered set a least upper bound is taken, we add this set as an index to the symbol; for example, ∨AX denotes the least upper bound of X in the partially ordered set A.

Dans un récent article [2, p. 379], R. M. Robinson a émis une conjecture intéressante sur le diamètre transfini des ensembles compacts et symétriques du plan. La conjecture est la suivante:

Soit E un ensemble compact de points du plan, symétrique par rapport á l'axe réel R. Pour n ≥ 2, choisissons n points z1, …, zn de E et posons xi = zi,   pour i=1, 2,…, n.

Soient:

A well known theorem of Hasse [1] says that every quadratic form in at least 5 variables over the field Qp of p-adic numbers has a nontrivial zero. This fact has led Artin to make the conjecture

(C): "Every form over Qp of degree d in n > d2 variables has a non-trivial zero." However, a counterexample has been provided by Terjanian [2] in the case d=4.

The case d=2 is distinguished by the fact that every quadratic form may be "diagonalized", i.e., assumed to be of the type Σ aiX2i. One is therefore led to the weaker conjecture

(C): "Every form f= Σ aiXdi over Qp in n > d2 variables has a nontrivial zero in Qp,"

which still generalizes Hasse's theorem.

Un ensemble de Wiener-Hopf est une partie S de la droite réelle R tel que

1. (i) S+ et S- sont non-vides

2. (ii) S+ + S- ⊂ S

où S- ∪ S0 ∪ S+ est la décomposition de S en parties négative, nulle, et positive.

On remarque que ces ensembles présentent une parenté avec les semi-groupes de R. Ainsi, dans [1], est-il démontré que si S n'est pas concentré sur un multiple des entiers, S est dense dans un intervalle.

In [2] it is shown that an n × n partial latin square with n — 1 cells occupied on the main diagonal can be completed to a latin square. We can use the technique in [2] to prove the following result.

Let P be an n × n partial latin square based on 0,1, 2, …, n — 1 satisfying the above conditions, and let (x0, y0), (x1, y1), …, (xn-2, yn-2) De the occupied cells where y0, y1, … yn-2 are distinct.

In [1] it was shown that a continuous function of bounded variation on the real line determined a Method II outer measure for which the Borel sets were measurable and the measure of an open interval was equal to the total variation of f over the interval. The monotone property of measures implied that if an open interval I on which f was not of bounded variation contained subintervals on which f was of finite but arbitrarily large total variation then the measure of I was infinite. Since there are continuous functions that are not of bounded variation over any interval (e.g. the Weierstrasse nondifferentiable function) the general case was not resolved.