From Toeplitz Eigenvalues through Green's Kernels to Higher-Order   Wirtinger-Sobolev Inequalities
  The paper is concerned with a sequence of constants which appear in several problems. These problems include the minimal eigenvalue of certain positive definite Toeplitz matrices, the minimal eigenvalue of some higher-order ordinary differential operators, the norm of the Green kernels of these operators, the best constant in a Wirtinger-Sobolev inequality, and the conditioning of a special least squares problem. The main result of the paper gives the asymptotics of this sequence. 
A. Boettcher and H. Widom