Sequences of numbers have long fascinated both amateur and professional mathematicians. Many people are familiar with the Fibonacci sequence, in which each new term is the sum of the previous two terms: 1, 1, 2, 3, 5, 8, 13, 21, 34, 55, 89, and so on. More than 69,000 other sequences of interest to mathematicians are catalogued in Neil J.A. Sloane’s On-Line Encyclopedia of Integer Sequences at http://www.research.att.com/~njas/sequences/.
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Here’s a recently discovered example that has prompted some serious mathematical investigation.