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arXiv · 1504.03980

Torus fixed points in Schubert varieties and normalized median Genocchi numbers

Xin Fang·Ghislain Fourier
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Abstract

We give a new proof for the fact that the number of torus fixed points for the degenerated flag variety is equal to the normalized median Genocchi number, using the identification with a certain Schubert variety. We further study the torus fixed points for the symplectic degenerated flag variety and develop a combinatorial model, symplectic Dellac configurations, so parametrize them. The number of these symplectic fixed points is conjectured to be the median Euler number.

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Xin Fang, Ghislain Fourier. 2015-04-15. Torus fixed points in Schubert varieties and normalized median Genocchi numbers. https://arxiv.org/abs/1504.03980

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