[math-fun] Triple denests while inner fails

It's clear that √(a+√(b+√c)) can't completely denest unless √(b+√c) does. Failing that, I'd've expected nothing better than √(b+√c) + √d + √e + ..., i.e., the √(b+√c) would act atomically, like √integer. But Sqrt[1/2 - Sqrt[-2 + Sqrt[5]]] == 1/2 Sqrt[-1 + Sqrt[5]] + 1/4 (Sqrt[2] - Sqrt[10]) --rwg