tech.rsqn.useful-things math-and-data 1.0.81 1.0.81 1.0.58 1.0.59 1.0.60 1.0.61 1.0.62 1.0.63 1.0.64 1.0.68 1.0.69 1.0.70 1.0.71 1.0.72 1.0.75 1.0.76 1.0.77 1.0.78 1.0.81 20260218221722