Bounded invertible reduction conjecture for Toeplitz factorizations

Let ToepnInv\mathrm{Toep}_n^{\mathrm{Inv}} denote the minimal number of Toeplitz factors needed to factor every invertible n×nn\times n matrix. A matrix is understood to be factored as a product of matrices, and Toepn\mathrm{Toep}_n is the maximal Toeplitz number among all n×nn\times n matrices.

Bounded invertible reduction conjecture. There exists a constant C>0C>0 such that every matrix can be expressed as a product of an invertible matrix and CC Toeplitz matrices. In particular,

ToepnToepnInv+C.\mathrm{Toep}_n\leq\mathrm{Toep}_n^{\mathrm{Inv}}+C.

This would reduce the general factorization problem to the invertible case up to an additive constant. The paper proves that C=3C=3 suffices for n=3n=3 and n=4n=4, while the existence of a dimension-independent constant remains open.

Sources & referencesView supporting material

Primary source

Ignacio García-Marco, Irene Márquez-Corbella and Daniel Seco, “On the minimum number of Toeplitz factors of a matrix”, arXiv:2506.16432 (2025).

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.