New functional dilogarithm identities and sine-Gordon Y-systems

The sine-Gordon Y-systems and those of the minimal $M_{p,q}+\phi_{13}$ models are determined in a compact form and a correspondence between the rational numbers and a new infinite family of multi-parameter functional equations for the Rogers dilogarithm is pointed out. The relation between the TBA-duality and the massless RG fluxes in the minimal models recently conjectured is briefly discussed.