Function sine_over_gamma_ratio 

fn sine_over_gamma_ratio(v: f64, order: i32, sin: f64) -> Scaled

sin(νπ) Γ(ν - μ + 1)/Γ(ν + μ + 1); outside the caller domain (μ > round(ν)) the vanishing factor ν - round(ν) of the gamma ratio is cancelled against sin(νπ).