NOVA: The Great Math Mystery (9 p.m., UNC-TV) – NOVA explores math's power across the centuries, from the first wireless radio transmissions to the landing of rovers on Mars. In one segment, Duke professor Elizabeth Brannon shares the latest research on how well lemurs understand quantity and the abstract essence of numbers using fascinating computer recognition tests.
Also on tonight . . .
Arrow (8 p.m., CW) –With Lance still targeting the Arrow, Felicity insists that Oliver keep a low profile. Also, a meta-human who uses blasts of energy and plasma to kill people terrorizes the city.
The Middle (8 p.m., ABC) – On his 21st birthday, Axl refuses to come home and help Mike move a freezer, and Brick cops a bad attitude with Frankie.
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The Americans (10 p.m., FX) – In the season’s penultimate episode, Philip and Elizabeth must work a formidable Mujahideen commander, while Martha hosts an unexpected guest and Paige acts out.
Million Dollar Listing: New York (10 p.m., Bravo) – In the Season 4 opener, Fredrick holds an open house attended by longtime rival Ryan and frenemy Luis, who shows no interest in mending fences with his adversaries.
R&B Divas LA (10 p.m., TV One) – In the Season 3 finale, the girls perform at a cancer benefit show.