Quota Rule

A Recurrence Relation between the function $Q$ arising in Quota Systems,

$$Q(n,r)=Q(n-1,r-1)+Q(n-1,r).$$

References

Young, S. C.; Taylor, A. D.; and Zwicker, W. S. ``Counting Quota Systems: A Combinatorial Question from Social Choice Theory.'' Math. Mag. 68, 331-342, 1995.