Has anyone ever did decent in undergrad as a math major (3.5 GPA) with little to no research at all and graduate courses, then did a T10-20 pure math masters, and went to a T10-20 pure math PhD? Is this even possible? It seems like the people who get into T10-20 pure math PhDs have been doing research from day one of undergrad and have completed 20+ graduate math courses by the time they graduate.