GROTHENDIECK POLYNOMIALS AND QUIVER FORMULAS By ANDERS S. BUCH, ANDREW KRESCH, HARRY TAMVAKIS, and ALEXANDER YONG
نویسندگان
چکیده
Fulton’s universal Schubert polynomials give cohomology formulas for a class of degeneracy loci, which generalize Schubert varieties. The K-theoretic quiver formula of Buch expresses the structure sheaves of these loci as integral linear combinations of products of stable Grothendieck polynomials. We prove an explicit combinatorial formula for the coefficients, which shows that they have alternating signs. Our result is applied to obtain new expansions for the Grothendieck polynomials of Lascoux and Schützenberger.
منابع مشابه
Stable Grothendieck Polynomials and K-theoretic Factor Sequences
We give a nonrecursive combinatorial formula for the expansion of a stable Grothendieck polynomial in the basis of stable Grothendieck polynomials for partitions. The proof is based on a generalization of the EdelmanGreene insertion algorithm. This result is applied to prove a number of formulas and properties for K-theoretic quiver polynomials and Grothendieck polynomials. In particular we for...
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