What are situations where one can conclude that all entries of an intersection form are divisible by an integer? More precisely: $F \subset S$ is a proper connected (usually reducible) ...
Which statement do people usually call the Decomposition Theorem, and what is the precise reference for it?
Which statement is usually called the Decomposition Theorem (for perverse sheaves)? Is this (roughly): a proper pushforward of an intersection complex could be decomposed into a direct sum of ...