In mathematics, particularly matrix theory, a Stieltjes matrix, named after Thomas Joannes Stieltjes, is a real  symmetric positive definite matrix with nonpositive off-diagonal entries.
A Stieltjes matrix in mathematics, particularly within the domain of matrix theory, is characterized by being a real symmetric positive definite matrix with nonpositive off-diagonal elements, as recognized by Thomas Joannes Stieltjes.