  In this paper we revisit a generalised crossing equation that follows from
harmonic analysis on the conformal group, and is of particular interest for the
cosmological bootstrap programme. We present an exact solution to this
equation, for dimensions two or higher, in terms of 6j symbols of the Euclidean
conformal group, and discuss its relevance. In the process we provide a
detailed derivation of the analogue of the Biedenharn-Elliot identity for said
6j symbols.
