While some of the safes in Mafia: The Old Country need to be opened to move on with the main plot, others require a little more work to find them. The one thing they all have in common, however, is ...

Brunnian links are a type of nontrivial link – or knot – where multiple linked loops become unlinked if a single loop is cut or removed. Beyond ‘fun’ disentanglement toys and a tantalizing subject of ...