Chromatic symmetric functions and change of basis

التفاصيل البيبلوغرافية
العنوان: Chromatic symmetric functions and change of basis
المؤلفون: Sagan, Bruce E., Tom, Foster
سنة النشر: 2024
المجموعة: Mathematics
مصطلحات موضوعية: Mathematics - Combinatorics, Primary 05E05, Secondary 05C15, 05C31, 05E10
الوصف: We prove necessary conditions for certain elementary symmetric functions, $e_\lambda$, to appear with nonzero coefficient in Stanley's chromatic symmetric function as well as in the generalization considered by Shareshian and Wachs. We do this by first considering the expansion in the monomial or Schur basis and then performing a basis change. Using the former, we make a connection with two fundamental graph theory invariants, the independence and clique numbers. This allows us to prove nonnegativity of three-column coefficients for all natural unit interval graphs. The Schur basis permits us to give a new interpretation of the coefficient of $e_n$ in terms of tableaux. We are also able to give an explicit formula for that coefficient.
Comment: 21 pages, 5 figures
نوع الوثيقة: Working Paper
URL الوصول: http://arxiv.org/abs/2407.06155
رقم الأكسشن: edsarx.2407.06155
قاعدة البيانات: arXiv