The invariant of Chen-Nagano on flag manifolds

Sánchez, Cristián U.

doi:10.1090/S0002-9939-1993-1163336-1

The invariant of Chen-Nagano on flag manifolds
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by Cristián U. Sánchez

Proc. Amer. Math. Soc. 118 (1993), 1237-1242

DOI: https://doi.org/10.1090/S0002-9939-1993-1163336-1

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Abstract:

In this paper an extension of the $2$-number $({\# _2}(M))$ of a symmetric space is given for $k$-symmetric spaces. The new invariant is computed for flag manifolds which are not symmetric. It turns out to be equal to the Euler-Poincaré characteristic.

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