Simple is beautiful. This universal principle is valid in mathematics and geometry too!
Equation for three-leaved-rose (trifolium) in polar coordinates is
r = a cos (3θ )
where “a” is a constant and the angle θ is measured from the x-axis.
If you want one of the lobes to lie on the negative x-axis the equation is
r = -a cos (3θ )
r = a cos (nθ)
r = a sin (nθ)
has n leaves if n is odd.