What does unmarked array mean in math?

In mathematics, an "unmarked array" typically refers to a matrix or grid of numbers that does not have any specific labels or indices assigned to its rows and columns. This means the elements are presented in a structured format without explicit identification of their positions, focusing instead on the numerical relationships or patterns within the array itself. The term is often used in contexts such as combinatorics or data representation, where the arrangement of elements is significant but not their specific locations.