Fudgeflakes

The name fudgeflake has been applied to the directly self-similar cyclic trihextal. I extend the name to include the corresponding inversely self-similar tile, distinguishing them as the cis-fudgeflake and the trans-fudgeflake.

cis 1st order fudgeflake, cis-cyclotrimertrans 1st order fudgeflake, trans-cyclotrimer

The elements of the above figures can be considered as centred on 3 points of a hexagonal grid (e.g. at the Eisenstein integers e00, e10 and e11). I extend the concept of a fudgeflake to include additional c3-symmetric order 3n2 tiles formed from elements forming a d3-symmetric hexagonal array with n and n+1 elements alternatively on each side, particularising these as the nth order cis- and trans-fudgeflakes. These can equivalently by conceived of as being formed by adding elements (and reducing the size of each element to compensate) at the points on the hexagonal grid forming a ring around the points involved in the previous order tiles.

I conjecture that these two series of tiles have a countably infinite number of members, as there is no obvious reason why the construction should stop working at any point.

These fractals share the following properties

As n tends to infinity the attractor approaches a regular hexagon.

2nd order cis-fudgeflake2nd order trans-fudgeflake

3rd order cis-fudgeflake3rd order trans-fudgeflake

4th order cis-fudgeflake4th order trans-fudgeflake

5th order cis-fudgeflake5th order trans-fudgeflake

6th order cis-fudgeflake6th order trans-fudgeflake

7th order cis-fudgeflake7th order trans-fudgeflake

8th order cis-fudgeflake8th order trans-fudgeflake

9th order cis-fudgeflake9th order trans-fudgeflake

These obviously tile the plane with one copy in the unit cell. With the above orientations and placement of elements on a unit grid the tiling vectors are en0 + enn and en0 - e0n.

cis 1st order fudgeflake tilingtrans 1st order fudgeflake tiling

cis 2nd order fudgeflake tilingtrans 2nd order fudgeflake tiling

cis 3rd order fudgeflake tilingtrans 3rd order fudgeflake tiling

cis 4th order fudgeflake tilingtrans 4th order fudgeflake tiling

cis 5th order fudgeflake tilingtrans 5th order fudgeflake tiling

cis 6th order fudgeflake tilingtrans 6th order fudgeflake tiling

cis 7th order fudgeflake tilingtrans 7th order fudgeflake tiling

cis 8th order fudgeflake tilingtrans 8th order fudgeflake tiling

cis 9th order fudgeflake tilingtrans 9th order fudgeflake tiling

Source:

All are independently discovered, although I have since found copies of the 1st order cis- and trans-fudgeflakes on the web.

The fudgeflake can be traced back to C. Davis & D. Knuth, Number representations and dragon curves. J. of Recreational Mathematics 3: 66–81 & 133–149 (1970), many years before I found it on a systematic investigation of IFSs based on rings of elements. I must have seen it in Benoit Mandelbrot's The Fractal Geometry of Nature several years earlier as well.

References:

  1. Famous Fractals: Fudgeflake at ThinkQuest: geometric construction of boundary of cis-fudgeflake - could be implemented as 1st order IFS or L-System.
  2. Turtle Program for Fudgeflake, inter alia from G. Edgar:
  3. Fraktaltechnik (Fudgeflake): recursive geometric construction for cis-fudgeflake.
  4. various constructions for the fudgeflake from Larry Riddle
  5. "India": cis-fudgeflake, by William Gosper
  6. "continuum": trans-fudgeflake, by William Gosper

© 2000, 2017, 2018 Stewart R. Hinsley