[2] Gilbreath got a BS in mathematics at University of California, Los Angeles (UCLA).
Unlike a standard riffle, it preserves certain properties of the sequence of cards, leading to its use in magic tricks.
[4] But the principal only became well known after Martin Gardner wrote about it in his July 1972 "Mathematical Games column" in Scientific American.
Two other students, R. B. Killgrove and K. E. Ralston, took advantage of the state-of-the-art SWAC computer installed at UCLA and confirmed it for the first 63419 primes.
[6] Unknown to them, the same pattern had been observed many years earlier by François Proth, but it is by Gilbreath's name that the conjecture is now known.