Mathlean · Online math workspace
Lucas number calculator
Evaluate the Lucas sequence with initial values 2 and 1.
How to use this calculator
Replace 10 in LucasL; the tenth Lucas number is 123.
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
This is the standard Lucas-number sequence, not arbitrary Lucas sequences with user-chosen parameters.
Mathlean combines visual mathematical input with computation and canvas tools. Results depend on the expression and available engine support; check important answers independently.