Perfect numbers: 1, 6, 28, 496, 8128, ...
Characteristic: equal to sum of proper factors plus UNITY
28 is a perfect, triangular number. When we fit 28 circles onto the equilateral triangle and bind four such triangles into a tetrad, the resulting construct has 112 = 28 * 4 circles.
Algebraically, 108 is expressible as (1) x (2x2) x (3x3x3).
Geometrically, 108° is complement to the 72° angle; it is the measure of a single angle on the perimeter of a regular pentagon, and is an harmonic of 18°, hence related to the phi growth function.
'108' of these symbolic objects are known in Buddhist lore as earthly 'desires, defilements,or sins.' The '108' are also well-referenced in traditional Chinese medicine and martial arts.
The remaining four symbolic objects represent the defenders of the Dharma: the Myo-o, Tathagata, Jinas, Dhyani, or Vidyarja wisdom beings cited above. Understood geometrically, each wisdom being may be positioned at the center of a triangular face, or at a vertex.
The fifth and central wisdom being, known as Samantabhadra or Vairocana, is represented as the field of action for the others. Geometrically, it is the central nexus of the tetrad as we have depicted in our '5-cell recursive-polychoron' and 'viswa-vajra' models of infinitely nested spheres and tetrads.
This graphic explicitly depicts the 2D shell of a tetrad with inscribed circles, and suggests a tetrahedral pyramid comprised of spheres nesting tetrads in a recursive fashion.
The 2D presentation gives four equilateral triangles each comprised of 28 circles, each circle nesting a regular triangle. The central node of each large triangle is colored to illustrate how a tetrad embodies biaxial polarity. That is, a tetrahedron comprises two orthogonal axes that intersect at the central fifth vertex.
Interpreting this in 3D, we can imagine within the tetrahedron, a single spherically-nested tetrad positioned precisely between each vertex and the colored tetrad on the opposing face.
These five, the four colored tetrads, plus the central tetrad comprise a geometric metaphor for that which is represented by the jiu-dzu, or Japanese rosary. To wit, these five represent
Five Buddha of Wisdom
Five Buddha of Meditation
Five Dhyāni Buddha
Five Wisdom Tathagata
Five Godai Nyorai
Five Heavenly Kingshttp://www.onmarkproductions.com/html/godai-nyorai.shtml