fact: Definition halfiw : Qpos := (w / ((2#1) * N))%Qpos.
imports: List NPeano QArith Qabs Qpossec Qsums Qround Qmetric ZArith CRArith CRsum util.Qgcd Program uneven_CRplus stdlib_omissions.P stdlib_omissions.Z stdlib_omissions.Q Coq.ZArith.Zsqrt_compat