title: Bang's theorem
text: # Bang's theorem
  
  Bang's theorem may refer to:
  
  * The solution to Tarski's plank problem by Thøger Bang (1917–1997)
  * A special case of Zsigmondy's theorem, on unique divisors of Mersenne numbers, by Alfred Sophus Bang (1866–1942)
  * Bang's theorem on tetrahedra, posed by Alfred Sophus Bang (1866–1942)
  