The fractal illustrated above.
Exterior Snowflake
See also
Gosper Island, Koch Antisnowflake, Koch Snowflake, PentaflakeExplore with Wolfram|Alpha
References
Wagon, S. Mathematica in Action. New York: W. H. Freeman, pp. 193-195, 1991.Referenced on Wolfram|Alpha
Exterior SnowflakeCite this as:
Weisstein, Eric W. "Exterior Snowflake." From MathWorld--A Wolfram Web Resource. https://mathworld.wolfram.com/ExteriorSnowflake.html