The symmetry of intersection numbers in group theory

@article{Scott1998TheSO,
  title={The symmetry of intersection numbers in group theory},
  author={Peter Scott},
  journal={Geometry \& Topology},
  year={1998},
  volume={2},
  pages={11-29}
}
  • P. Scott
  • Published 2 December 1997
  • Mathematics
  • Geometry & Topology
For suitable subgroups of a nitely generated group, we dene the intersection number of one subgroup with another subgroup and show that this number is symmetric. We also give an interpretation of this number. 
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