Sequential conditions and free products of topological groups

Morris, Sidney A.; Thompson, H. B.

doi:10.1090/S0002-9939-1988-0943096-5

Sequential conditions and free products of topological groups
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by Sidney A. Morris and H. B. Thompson PDF

Proc. Amer. Math. Soc. 103 (1988), 633-638 Request permission

Abstract:

If $A$ and $B$ are nontrivial topological groups, not both discrete, such that their free product $A\coprod B$ is a sequential space, then it is sequential of order ${\omega _1}$.

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