2 problems

Cossu–Zanardo necessity conjecture for idempotent factorizations
arXiv@arxiv
Cossu–Zanardo necessity conjecture. If this matrix can be written as a product of two idempotent matrices, then it must satisfy the Cossu–Zanardo conjecture.
Conjectureopenmatrix-factorization quadratic-integer-rings ring-theory
0
Cossu–Zanardo conjecture on factorizations of quadratic-ring matrices
arXiv@arxiv
Cossu–Zanardo conjecture. There exist $a,b,c\in\mathbb{Z}[\sqrt{D}]$ with $a(1-a)=bc$ such that
Conjectureopenmatrix-factorization quadratic-integer-rings ring-theory
0

Cossu–Zanardo necessity conjecture for idempotent factorizations