Catalan number (English, noun)
expansion: Catalan number (plural Catalan numbers)
Senses:
glosses: In combinatorial mathematics, any of a sequence of natural numbers that occur in various counting problems, often involving recursively defined objects; the nᵗʰ Catalan number is equal to (2n choose n) over (n+1).
Forms:
form: Catalan numbers
tags: plural