Editing Sierpiński triangle (section)

===Towers of Hanoi===
The [[Towers of Hanoi]] puzzle involves moving disks of different sizes between three pegs, maintaining the property that no disk is ever placed on top of a smaller disk. The states of an {{mvar|n}}-disk puzzle, and the allowable moves from one state to another, form an [[undirected graph]], the [[Hanoi graph]], that can be represented geometrically as the [[intersection graph]] of the set of triangles remaining after the {{mvar|n}}th step in the construction of the Sierpiński triangle. Thus, in the limit as {{mvar|n}} goes to infinity, this sequence of graphs can be interpreted as a discrete analogue of the Sierpiński triangle.<ref>{{citation
 | last = Romik | first = Dan
 | arxiv = math.CO/0310109
 | doi = 10.1137/050628660
 | issue = 3
 | journal = SIAM Journal on Discrete Mathematics
 | mr = 2272218
 | pages = 610–62
 | title = Shortest paths in the Tower of Hanoi graph and finite automata
 | volume = 20
 | year = 2006| s2cid = 8342396
 }}.</ref>