Abstract: I will present a formula that expresses the Hankel determinants of a linear combination of length d+1 of moments of orthogonal polynomials in terms of a d x d determinant of the orthogonal polynomials. As a literature search revealed, this formula exists somehow hidden in the folklore of the theory of orthogonal polynomials as it is related to "Christoffel's theorem". In any case, it deserves to be better known and be presented correctly and with full proof. (During the talk I will explain the meaning of these somewhat cryptic formulations.) Subsequently, I will show some applications of the formula. I will close the talk by presenting a generalisation that is inspired by Uvarov's formula for the orthogonal polynomials of rationally related densities, again together with some - curious - applications. 

Zoom-Meeting beitreten: https://zoom.us/j/93778343609?pwd=YngwNmNLZWgxczRnYXNxdHZTSVdSdz09 
Meeting-ID: 937 7834 3609
Kenncode: BCfC2J