Lecomte and Ovsienko constructed SLn+1(R)-equivariant quantization maps Qλ for symbols of differential operators on λ-densities on RP n . We derive some formulas for the associated graded equivariant star products ★λ on the symbol algebra Pol(T* RP n ). These give some measure of the failure of locality. Our main result expresses (for n odd) the coefficients C p (·,·) of ★λ when λ = \(\frac{1}{2}\) in terms of some new SLn+1(C)-invariant algebraic bidifferential operators Z p (·,·) on T* CP n and the operators (E + n/2 ± s)−1 where E is the fiberwise Euler vector field and s ∈ {1, 2, ..., [p/2]}.