A well known formula for evaluating Toeplitz determinants with rationa
l generating functions due to Day [Trans. Amer. Math. Soc. 206 (1975),
224-245] is complemented by a little known formula involving determin
ant of reduced order. The latter formula is used to evaluate some Toep
litz determinants with special rational generating functions in terms
of the Barnes G-function and the Gauss hypergeometric function.