# Fibonacci numbers

[fee-boh-nah-chee]

- the unending sequence 1, 1, 2, 3, 5, 8, 13, 21, 34, … where each term is defined as the sum of its two predecessors.

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## Origin of Fibonacci numbers^{}

1890–95; after Leonardo Fibonacci, 13th-century Italian mathematician

Also called Fibonacci sequence.

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Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018