Definition

1. Noun:
   • A number in the Fibonacci sequence: A Fibonacci number is an integer that appears in the Fibonacci sequence, a series where each number is the sum of the two preceding ones, typically starting with 0 and 1.

Usage

• The term "Fibonacci number" is used in mathematics, computer science, and nature studies to describe specific integers from this famous sequence.
• It is a countable noun (e.g., "the tenth Fibonacci number").

Examples

• Noun:
  • 5 is a Fibonacci number because it appears in the sequence 0, 1, 1, 2, 3, 5, 8...
  • The ratio between consecutive Fibonacci numbers approximates the golden ratio.

Advanced Usage

• "n-th Fibonacci number": Refers to the number occupying the n-th position in the sequence.
  • Calculating the 100th Fibonacci number requires an efficient algorithm.

Variants and Related Words

• Fibonacci sequence (n): The entire infinite series of numbers generated by the Fibonacci rule.
  • The Fibonacci sequence is often observed in biological settings, such as the arrangement of leaves.

Synonyms

• Term in the Fibonacci series: A more descriptive synonym.
• Element of the Fibonacci progression: A formal mathematical synonym.

Noun

1. a number in the Fibonacci sequence