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Fibonacci series Definition

Fi·bo·nacci series (fē′bə näc̸hē)

noun

a sequence of integers in which each integer (Fibonacci number) after the second is the sum of the two preceding integers; specif., the series 1, 1, 2, 3, 5, 8, 13, . . .

Etymology: after L. Fibonacci, 13th-c. It. mathematician, who developed it