Asymptotic counting conjecture for q-matroids with fixed rank

Let sq(r,n)s_q(r,n), pq(r,n)p_q(r,n), and mq(r,n)m_q(r,n) denote respectively the numbers of sparse paving, paving, and all qq-matroids of rank rr on an nn-dimensional space over the finite field with qq elements, where qq is a prime power. For nonnegative functions, write f(t)≈g(t)f(t)\approx g(t) as t→∞t\to\infty when

lim⁡t→∞f(t)g(t)∈R>0.\lim_{t\to\infty}\frac{f(t)}{g(t)}\in\mathbb{R}_{>0}.

Asymptotic counting conjecture. For all r≥2r\geq 2 and prime powers qq, we have

log⁡(sq(r,n))≈log⁡(pq(r,n))≈log⁡(mq(r,n))≈q(n−r)(r−1)(n−r)\log(s_q(r,n))\approx\log(p_q(r,n))\approx\log(m_q(r,n))\approx q^{(n-r)(r-1)}(n-r)

as n→∞n\to\infty. The conjecture predicts that the number of sparse paving qq-matroids is already asymptotically as large as the numbers of paving and all qq-matroids in this fixed-rank regime, closing the gap between the current lower and upper bounds.

References

Primary source

Benjamin Jany, Relinde Jurrius and Rudi Pendavingh, “Counting q-Matroids”, arXiv:2606.20348 (2026).

Progress summary

Never refreshed

Nothing recorded yet. Refresh searches the literature and the public web for attempts on this problem, and writes the first summary here.

Solutions 0

No solutions have been posted yet.