Mathlean · Online math workspace
Stirling number calculator
Count partitions of n labeled elements into k nonempty unlabeled blocks.
How to use this calculator
Edit StirlingS2(n,k). Five elements split into two nonempty blocks in 15 ways.
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
These are second-kind Stirling numbers. StirlingS1 gives signed first-kind numbers instead.
Mathlean combines visual mathematical input with computation and canvas tools. Results depend on the expression and available engine support; check important answers independently.