Name this number equal to the number of sides of a trapezoid, parallelogram, or square.
This is the smallest number of which it can be said that every natural number can be written as the sum of this many perfect squares, which is based on a theorem named for Lagrange. This is also the largest number such that all polynomials with this degree can always be solved using radicals. Wolfgang Haken and Kenneth Appel proved that any planar map with contiguous regions and bordering regions with different colors can be drawn with this number of colors. This is also the number of faces of a tetrahedron. Name this number equal to the number of sides of a trapezoid, parallelogram, or square.
This is the smallest number of which it can be said that every natural number can be written as the sum of this many perfect squares, which is based on a theorem named for Lagrange.
4