In geometry, a myriagon is a polygon with 10000 sides or 10000-gon. Several philosophers have used the regular myriagon to illustrate issues regarding thought.
A regular myriagon is represented by Schläfli symbol {10000} and can be constructed as a truncated 5000-gon, t{5000}, or a twice-truncated 2500-gon, tt{2500}, or a thrice-truncaed 1250-gon, ttt{1250), or a four-fold-truncated 625-gon, tttt{625}.
The measure of each internal angle in a regular myriagon is 179.964°. The area of a regular myriagon with sides of length a is given by
Because 10000 = 24× 54, the number of sides is neither a product of distinct Fermat primes nor a power of two. Thus the regular myriagon is not a constructible polygon. Indeed, it is not even constructible with the use of neusis or an angle trisector, as the number of sides is neither a product of distinct Pierpont primes, nor a product of powers of two and three.
The regular myriagon has Dih10000dihedral symmetry, order 20000, represented by 10000 lines of reflection. Dih100 has 24 dihedral subgroups: (Dih5000, Dih2500, Dih1250, Dih625), (Dih2000, Dih1000, Dih500, Dih250, Dih125), (Dih400, Dih200, Dih100, Dih50, Dih25), (Dih80, Dih40, Dih20, Dih10, Dih5), and (Dih16, Dih8, Dih4, Dih2, Dih1). It also has 25 more cyclic symmetries as subgroups: (Z10000, Z5000, Z2500, Z1250, Z625), (Z2000, Z1000, Z500, Z250, Z125), (Z400, Z200, Z100, Z50, Z25), (Z80, Z40, Z20, Z10), and (Z16, Z8, Z4, Z2, Z1), with Zn representing π/n radian rotational symmetry.
Along the heavy deserted shores the twilight unfolds full pride
Black deep waters submit the grip of tide
Carry dragonships in front of thee in a deepred shady light
Comes from foreign shores a sea spread open and wide
Ships of fog with burning sails, a fleet of an requiem raise
Hear the elegy of sea-gulls, hear like ravens cry
Carry mens of virtue, kings and heroes in honour
Proud and might, inflame a fire, sing a farewell and take their soul up high
Up high stars fall, far the ravens call
Shout for ships dressed with fire to heavens wide halls
Fay behind crows eyes, woman of snow and ice
Under the roofs of Valhalla were warriors stand tall
Ships of fog with burning sails, a fleet of an requiem raise
Hear the elegy of sea-gulls, hear like ravens cry
Carry mens of virtue, kings and heroes in honour
Proud and might, inflame a fire, sing a farewell and take their soul up high