id: 06132026 dt: j an: 2013a.00672 au: Trenkler, Götz; Trenkler, Dietrich ti: The numerical range of the Luoshu is a piece of cake ‒ almost. so: Coll. Math. J. 43, No. 5, 371-376 (2012). py: 2012 pu: Mathematical Association of America (MAA), Washington, D.C. la: EN cc: H65 G75 ut: matrices; magic suares; Luoshu magic squares; numerical range ci: li: doi:10.4169/college.math.j.43.5.371 ab: Summary: The numerical range, easy to understand but often tedious to compute, provides useful information about a matrix. Here we describe the numerical range of a $3 \times 3$ magic square. Applying our results to one of the most famous of those squares, the Luoshu, it turns out that its numerical range is a piece of cake ‒ almost. rv: