“…It is proved in [96] (though this was probably already known to Rauzy) that the rational numbers (T n /T n+1 , T n−1 /T n+1 ) provide the best possible simultaneous approximation of (1/β, 1/β 2 ) if we use the distance to the nearest integer defined by a particular norm, i.e., the so-called Rauzy norm; recall that if R d is endowed with the norm ||·||, and if θ ∈ T d , then an integer q 1 is a best approximation of θ if |||qθ||| < |||kθ||| for all 1 k q − 1, where ||| · ||| stands for the distance to the nearest integer associated with the norm || · ||. Furthermore, the best possible constant inf{c ; q 1/2 |||q 1/β, 1/β 2 ||| < c for infinitely many q} is proved in [96] to be equal to (β 2 +2β+3) −1/2 . This approach is generalised in [176] to cubic Pisot numbers with complex conjugates satisfying the finiteness property (F) (see Section 3.3).…”