The repressilator was described and implemented in E. coli in [1]. A simplified version of Elowitz and Leibler's mathematical model is implemented here; we omit consideration of mRNA and focus exclusively on the protein (repressor) concentrations. The parameters of this implementation are: the ratio

of the repressor production rate at a concentration of 1 to the repressor degradation rate, and the Hill function exponent

, which specifies the cooperativity of the repressor activity. It is possible to show that sustained oscillations occur for values of

approximately greater than

. This implies that sustained oscillations can be achieved at small values of

for large values of

, but only at large values of

for smaller values of

. Interestingly, it is not possible to achieve sustained oscillations at all for

, irrespective of the values of

, which is borne out in the Demonstration.