Each of these rules will be called a Gauss-Christoffel quadrature formula if it has maximum degree of exactness, i.e. if (1.1) is an exact equality whenever / is a polynomial of degree 2n — 1. It is a well-known fact, due to Christoffel [3], that such quadrature formulas exist uniquely, provided the weight function w(x) is nonnegative, integrable with /* w(x)dx > 0, and such that all its moments

A balanced word is one in which any two factors of the same length contain the same number of each letter of the alphabet up to one. Finite binary balanced words are called Sturmian words. A Sturmian word is bispecial if it can be extended to the left and to the right with both letters remaining a Sturmian word. There is a deep relation between bispecial Sturmian words and Christoffel words, th...

of the Dissertation The Ahlfors Iteration for Conformal Mapping by Christopher Michael Green Doctor of Philosophy in Mathematics Stony Brook University 2011 The Riemann Mapping Theorem states that for any proper, simply connected planar domain there exists a conformal mapping from the disk onto the domain. But can this map be explicitly described? For general domains, there is no obvious answer...

Let ω be a regular measure on the unit circle and let p > 0. We establish asymptotic behavior, as n→∞, for the Lp Christoffel function λn,p (ω, z) = inf deg(P )≤n−1 ∫ π −π ∣∣P (eiθ)∣∣p dω (θ) |P (z)| at Lebesgue points z on the unit circle, where ω′ is lower semi-continuous. While bounds for these are classical, asymptotics have never been established for p 6= 2. The limit involves an extremal ...

We characterize conjugation classes of Christoffel words (equivalently of standard words) by the number of factors. We give several geometric proofs of classical results on these words and sturmian words. Mathematics Subject Classification. 68R15.

We prove some new combinatorial properties of the set PER of all words w having two periods p and q which are coprimes and such that w = p + q 2 [4,3]. We show that aPERb U {a, b} = St n Lynd, where St is the set of the finite factors of all infinite Sturmian words and Lynd is the set of the Lyndon words on the alphabet {a, b}. It is also shown that aPERb U {a, b} = CP, where CP is the set of C...