N PATHS + DISTINCT REVERSES 2 2 + 0, namely, S, R 3 2 + 1, namely, SRRSR, RRSRR 4 3 + 3, namely: SRR RSR SRR RSR RRS RSR RSR RR RSR SRR RSR RRS RSR RRS RSR RR SRR RSR RRS RRS RSR RRS RRR SRPROBLEM: A questionable program said there are none for N = 5; is this so?