A two-parameter recursion formula for scalar field theory

We present a two-parameter family of recursion formulae for scalar field theory. The first parameter is the dimension (D). The second parameter (ζ) allows one to continuously extrapolate between Wilson's approximate recursion formula and the recursion formula of Dyson's hierarchical model. We show numerically that at fixed D, the critical exponent γ depends continuously on ζ. We suggest the use of the ζ-independence as a guide to construct improved recursion formulae. (author). Letter-to-the-editor