Specializations of Schur functions at consecutive integers - MathOverflow most recent 30 from http://mathoverflow.net2013-05-26T07:53:36Zhttp://mathoverflow.net/feeds/question/549http://www.creativecommons.org/licenses/by-nc/2.5/rdfhttp://mathoverflow.net/questions/549/specializations-of-schur-functions-at-consecutive-integersSpecializations of Schur functions at consecutive integersArmin Straub2009-10-15T02:40:16Z2009-11-04T12:00:19Z
<p>Given a partition λ = (λ<sub>1</sub>, λ<sub>2</sub>, ..., λ<sub>n</sub>) denote with s<sub>λ</sub> the associated Schur function.
There exists a nice product formula for the principal specializations:
<p>s<sub>λ</sub>(1, q, q<sup>2</sup>, ..., q<sup>n-1</sup>) = Π<sub>i<j</sub> (q<sup>λ<sub>i</sub>+n-i</sup> - q<sup>λ<sub>j</sub>+n-j</sup>) / (q<sup>j-1</sup> - q<sup>i-1</sup>).
<p>Is a similar evaluation known for specializations of the type s<sub>λ</sub>(1, 2, ..., n)?</p>
http://mathoverflow.net/questions/549/specializations-of-schur-functions-at-consecutive-integers/4061#4061Answer by Greg Kuperberg for Specializations of Schur functions at consecutive integersGreg Kuperberg2009-11-04T07:14:41Z2009-11-04T07:14:41Z<p>Let's take the strictest meaning of "similar evaluation", i.e., a product formula. The by the remark, the answer is probably no, because for instance the Stirling number s(9,3) = 118124 = 2*2*29531.</p>
<p>A different meaning is whether there is some explicit combination of nested sums and products for a Schur evaluation at consecutive integers. I don't know the answer to that. Unlike for a straight product formula, it is difficult to look for such formulas or rule them out.</p>
<p>The loosest possible meaning is whether there is an efficient way to evaluate s<sub>λ</sub>(1, 2,...,n). The answer to that is an easy yes, because you can use the Jacobi-Trudi determinant.</p>