As easy as 1, 1, 2, 3…

It's a bit of a fib that Fibonacci, the 13th-century Italian math whiz, was the first to sketch out a number sequence by adding each number to the preceding number: 1, 1, 2, 3, 5, 8, 13, and so on forever. In fact, Hindu scholars described the sequence centuries before Fibonacci, and they probably weren't the first to figure it out either. But in any case, each November 23—that is, 11/23—we celebrate the infinite series known as the Fibonacci sequence.
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