Alternating Delegations
Five American diplomats and five British diplomats (all ten distinct people) sit at a round table with ten seats, so that nationalities alternate around the table. Seatings differing only by a rotation are the same; mirror images are different. How many seatings are possible? Give an integer.
Related problems
Source: Classic counting exercise in wide circulation; no traceable original source. Statement written for AxiomIQ.