Atriphtaloid

An atriphtaloid with a = 3 and b = 2

An atriphtaloid, also called an atriphtothlassic curve, is type of sextic plane curve. It is given by the equation

x^4(x^2+y^2)-(ax^2-b)^2=0, \,

where a and b are positive numbers.

References

Weisstein, Eric W., "Atriphtaloid", MathWorld.