Mathlean · Online math workspace
Catalan number calculator
Count Catalan structures such as balanced parenthesis arrangements.
How to use this calculator
Replace the nonnegative index. The fifth Catalan number is 42.
Tap the math below to edit it and see the result. Once a result is ready, press Tab on a hardware keyboard to accept it. Outside a matrix, Return completes the line; the phone math keyboard has the same Return action.
Try it here
Interactive tools require JavaScript. You can read the guide and example without it.
What to know
The interpretation depends on which combinatorial structure you count; this page returns the sequence value.
Mathlean combines visual mathematical input with computation and canvas tools. Results depend on the expression and available engine support; check important answers independently.