Informal Definition
Informally, the kth Betti number refers to the number of unconnected k-dimensional surfaces. The first few Betti numbers have the following intuitive definitions:
- b0 is the number of connected components
- b1 is the number of two-dimensional or "circular" holes
- b2 is the number of three-dimensional holes or "voids"
Read more about this topic: Betti Number
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