English

Rational Exponents for Generalized Tur\'an Numbers

Combinatorics 2025-10-27 v2

Abstract

The generalized Tur\'an number ex(n,H,F)\text{ex}(n,H,\mathcal{F}) denotes the maximum number of copies of HH in an nn-vertex graph which contains no copies of any graph in a family F\mathcal{F} of graphs. The generalized rational exponents conjecture states that for every rational r1r\geq 1 there exist graphs H,FH,F such that ex(n,H,{F})=Θ(nr)\text{ex}(n,H,\{F\})=\Theta(n^r). We extend a result of Bukh and Conlon to show that for every non-empty graph HH on v2v\geq 2 vertices and every rational rr in the interval [v1,v][v-1,v] there exists a finite family Fr\mathcal{F}_r such that ex(n,H,Fr)=Θ(nr)\text{ex}(n,H,\mathcal{F}_r)=\Theta(n^r).

Keywords

Cite

@article{arxiv.2510.19621,
  title  = {Rational Exponents for Generalized Tur\'an Numbers},
  author = {Bas van der Beek and Anurag Bishnoi},
  journal= {arXiv preprint arXiv:2510.19621},
  year   = {2025}
}

Comments

The main result is false as the lower bound fails due to a calculation error at the top of page 7 where N=q^b is used instead of the correct N=q^{be}

R2 v1 2026-07-01T06:59:51.777Z