On squares of squares II

On Packing Squares with Equal Squares

The following problem arises in connection with certain multidimensional stock cutting problems : How many nonoverlapping open unit squares may be packed into a large square of side a? Of course, if a is a positive integer, it is trivial to see that a2 unit squares can be successfully packed . However, if a is not an integer, the problem becomes much more complicated . Intuitively, one feels th...

Irreducibility of Tensor Squares, Symmetric Squares and Alternating Squares

We investigate the question when the tensor square, the alternating square, or the symmetric square of an absolutely irreducible projective representation V of an almost simple group G is again irreducible. The knowledge of such representations is of importance in the description of the maximal subgroups of simple classical groups of Lie type. We show that if G is of Lie type in odd characteris...

Unifying Least Squares, Total Least Squares and Data Least Squares

The standard approaches to solving overdetermined linear systems Ax ≈ b construct minimal corrections to the vector b and/or the matrix A such that the corrected system is compatible. In ordinary least squares (LS) the correction is restricted to b, while in data least squares (DLS) it is restricted to A. In scaled total least squares (Scaled TLS) [15], corrections to both b and A are allowed, ...

Properties of Magic Squares of Squares

A problem due to Martin LaBar is to find a 3x3 magic square with 9 distinct perfect square entries or prove that such a magic square cannot exist (LaBar [1]). This problem has been tied to various domains including arithmetic progressions, rational right triangles, and elliptic curves (Robertson [2]). However, there are some interesting properties that can be derived without ever leaving the do...

Translative Packing of Unit Squares into Squares