Catalan Numbers Calculator

Calculate numbers that appear in various combinatorial problems

Result

C(n)
=
-

About Catalan Numbers

Catalan numbers form a sequence of natural numbers that occur in various counting problems, often involving recursively defined objects.

The first few Catalan numbers are:

  • C(0) = 1
  • C(1) = 1
  • C(2) = 2
  • C(3) = 5
  • C(4) = 14

Catalan numbers appear in many counting problems, including:

  • Number of ways to properly parenthesize n pairs of parentheses
  • Number of ways to triangulate a convex polygon with n+2 sides
  • Number of binary trees with n nodes
  • Number of paths on a grid that don't cross the diagonal

The formula for the nth Catalan number is:

\[C_n = \frac{1}{n+1}\binom{2n}{n}\]

Note: Catalan numbers grow exponentially. Our calculator can handle values up to n = 100.