Sierpinski Triangle: Equilateral or Isosceles?

[omega-centauri]

Is the Sierpinski triangle composed of equilateral or isosceles triangles? I've seen references for both but I have a student asking which one it is... any help is here greatly appreciated.

Isosceles example: http://ieeexplore.ieee.org/xpl/login.jsp?tp=&arnumber=5524998&url=http%3A%2F%2Fieeexplore.ieee.org%2Fiel5%2F5492939%2F5524731%2F05524998.pdf%3Farnumber%3D5524998

Thanks in advance!

 

[micromass]

Doesn't matter, all kind of triangles can be used.

 

[symbolipoint]

Visual comfort and readability would correlate with isosceles. Bilateral symmetry is important. Equilateral also would work well.