Lacunary interpolation for entire functions

Interpolation and Approximation by Entire Functions

In this note we study the connection between best approximation and interpolation by entire functions on the real line. A general representation for entire interpolants is outlined. As an illustration, best upper and lower approximations from the class of functions of fixed exponential type to the Gaussian are constructed. §1. Approximation Background The Fourier transform of φ ∈ L(R) is define...

Interpolation of entire functions, product formula for basic sine function

q-Taylor theorems, polynomial expansions, and interpolation of entire functions

We establish q-analogues of Taylor series expansions in special polynomial bases for functions analytic in bounded domains and for entire functions whose maximum modulus Mðr; f Þ satisfies jln Mðr; f ÞjpA ln r: This solves the problem of constructing such entire functions from their values at 1⁄2aq þ q =a =2; for 0oqo1: Our technique is constructive and gives an explicit representation of the s...

Interpolation of Shifted-Lacunary Polynomials [Extended Abstract]

Given a “black box” function to evaluate an unknown rational polynomial f ∈ Q[x] at points modulo a prime p, we exhibit algorithms to compute the representation of the polynomial in the sparsest shifted power basis. That is, we determine the sparsity t ∈ Z>0, the shift α ∈ Q, the exponents 0 ≤ e1 < e2 < · · · < et, and the coefficients c1, . . . , ct ∈ Q \ {0} such that f (x) = c1(x − α)1 + c2(...

Lacunary Partition Functions

We combine the theory of Bailey chains and the theory of binary quadratic forms to show that there are large classes of q-series which are not theta series but whose coefficients are almost all 0. We interpret some examples in terms of simple partition functions.