It was the duplicates...

That is sad to hear, you are very close. But keep in mind that the kata is not about which numbers, just that a number is found.

Edit: nvm, be aware of duplicates

Every kata you get a certain amount of computation time, depending on the language used. If you time out, your code is not efficient or the algorithm you used is not optimal.

Use memoization instead of hardcoding the solution: https://www.youtube.com/watch?v=Qk0zUZW-U_M