Euler Sudoku The symbols e, π, i, 0, 1, f, Σ, φ, and γ must each appear exactly once in each row, column, and 3x3 block. (Euler may have invented sudoku)

Euler Circuits and Euler Paths. In this video I discuss the ideas of: paths, multigraphs, euler paths, euler circuits, the necessary and sufficient condition for a graph to have an euler path or euler circuit, along with an applied problem.

## Euler–Mascheroni constant