Numerologically, 'Nothing' equals 6 - six squares make the shape of a cube.
'Nothing is Nothing' equals 616, which reduces to 13, then 4 - 4 lines make a square. Each single line has six directions based on 3D orientation - up/down, left/right and forward/backward - and six key visual features: straight or curved, thick or thin, monochromatic or coloured.
'Nothing-Is-Limbo' also equals 616>13>4 - the sign of the square, six of which make a cube. Numerology is not scientific.
However, mathematically, the sum of the squares of the factorials of 2,3,4 -(2!)^2 + (3!)^2 + (4!)^2 - i.e. 4+36+576 - is 616, an optimal code for the hypercube (tesseract)- a single 4-dimensional object, represented by a six-sided inner cube contained within a six-sided outer cube. A single tesseract has 36 2-D shapes - 30 on the outside (including six squares) and six squares on the inside - and 36 (6x6) is the square of 6. In short, the hypercube (tesseract) is an intuitive and visual symbol of nothingness, because of its 6-1-6 (inner-gestalt-outer) structural properties, among other things. You can see a blue example at the top of this page