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Pradeep Mutalik and Quanta readers explore an open question about prime numbers: What is the lowest valued, longest consecutive sequence of integers that are divisible by a set of prime numbers?

Prime numbers are endlessly fascinating to number theorists and math enthusiasts. This month’s puzzle explores primes by cooking up a whimsical dish of grilled snake ribs.

The mathematical concept of parity and the fatal flaw of serial multiplication can help explain why having two sexes usually works better than having one or three.

Asexual reproduction can produce twice as many offspring as sexual reproduction without the hassle of finding and courting a mate. So why do most complex animals have two sexes? Why not three?

Like scientific puzzles, Bongard problems can lead you through a frustrating blind search until you find that simple, elegant rule that fits a seemingly random pattern.

For your frustration, joy and entertainment, our puzzle challenges you to find general patterns or rules based on seemingly random, specific examples.

How Darwinian natural selection can produce and sustain a Lamarckian “inheritance of acquired characteristics.”

Answering three questions can help reveal how the “inheritance of acquired characteristics” fits into modern evolutionary theory.

There’s more than one good way to bring order to our unruly, seemingly arbitrary calendar.