Cannabis curve
There is a special page on Wolfram MathWorld dedicated to a very specific equation in polar coordinates.
r(θ) = a·[1 + 9/10·cos(8θ)]·[1 + 1/10·cos(24θ)]·[9/10 + 1/10·cos(200θ)]·(1 + sin θ)
I started wondering: is there something similar for a Christmas tree in polar coordinates?