A counter meant to register successes is locked for exactly r-1 epochs following a registration so the occurrence of a success at epoch n would be registered if no registration of one occurred in the preceding r-1 epochs. Upon a registration of a success at epoch n the mechanism would then be locked for epochs n+1 through n+r-1, so that a success could not be registered during any of these. A success would be registered at the n+r th epoch if it occurred since the counter would then be free. Let wn be the probability the counter is free (will register a success if one occurs ) at epoch n. If the probability of success p lies in (0,1) then there is, for each M , 0 < M < 1, greater than the reciprocal of the smallest magnitude of those roots of 1- ( q z + p zr) = 0 outside the unit circle in the complex plane, a finite K such that for all n
while for for every M less than that reciprocal there is no choice of real K for which this holds.
This is but one example of the application of the results on convergence rates of renewal sequences.