Photos of the Day: Photos of the day 05/21
In Pictures: Sinkholes around the world
In Pictures: What happened to the green revolution in Iran?
In Pictures: Facing the devastation of the Oklahoma tornadoes
In Pictures: Sandy: Chronicle of an unrelenting storm
Photos of the Day: Photos of the day 05/20
In Pictures: Weather extremes 2013
In Pictures: The Israeli separation barrier: A West Bank wall
In Pictures: Derby Day devotees, Kenyan style
The Google homepage today honors the mathematician Leonhard Euler, who was born 306 years ago today.
Matthew Shaer /
April 15, 2013
The Google homepage today features a scrap of paper covered in pencil-drawn equations, including a polyhedron formula, V-E+F=2.