## The index number of an $R$-space: An extension of a result of M.Takeuchi’s

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- by Cristián U. Sánchez
- Proc. Amer. Math. Soc.
**125**(1997), 893-900 - DOI: https://doi.org/10.1090/S0002-9939-97-03517-X
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## Abstract:

M. Takeuchi proved the following nice result: The “two-number” of a symmetric $R$-space is equal to the sum of the Betti numbers of the space with coefficients in $Z_2$. In the present paper an extension of this result is given for general $R$-spaces.## References

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## Bibliographic Information

**Cristián U. Sánchez**- Affiliation: Fa. M.A.F., Universidad de Córdoba, Ciudad Universitaria, 5000, Córdoba, Argentina
- Email: csanchez@mate.uncor.edu
- Received by editor(s): August 5, 1994
- Received by editor(s) in revised form: June 12, 1995
- Additional Notes: The author’s research was partially supported by CONICET and CONICOR, Argentina
- Communicated by: Roe W. Goodman
- © Copyright 1997 American Mathematical Society
- Journal: Proc. Amer. Math. Soc.
**125**(1997), 893-900 - MSC (1991): Primary 53C30; Secondary 53C35
- DOI: https://doi.org/10.1090/S0002-9939-97-03517-X
- MathSciNet review: 1343722