As easy as 1, 1, 2, 3…

It's a bit of a fib that Fibonacci, the 13th-century Italian mathematician, was the first to create a 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 him - and they probably weren't the first to figure it out either. Regardless, 23 November, which is written 11/23 in the US style, is the day people celebrate the infinite series known as the Fibonacci sequence.
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