[math-fun] Can a nonconstant continuous function on the reals

assume only rational values? Related puzzle: Find an x in closed form s.t. CantorStaircase[x] is irrational. --rwg Spoiler: "2/)]2/1 ,0 ,3[atehTcitpillE + 1-( == ]]3/1 ,0 ,3[atehTcitpillE + 1-[esacriatSrotnaC"