I don't remember this kata at all, but I see lots of other similar solutions... I'm not sure how I came up with this.

Can you describe the solution?

I've added random tests.

Neither of these solutions should work, anymore.

Most of the submitted solutions were not actually running most of the tests because Mocha was exiting early. I've added a Promise.race wrapper, which will prevent Mocha from exiting early. Most of the submitted solutions are now failing.

None of the submitted solutions can unwrap more than one layer of the equivalent of Promise.resolve/Promise.reject (including Promise.resolve(Promise.resolve(x)), Promise.resolve(Promise.reject(x)) and Promise.reject(Promise.resolve(x))), which clearly means the tests are too weak.

Also, there are no actual random tests. The only randomness in the tests is the fixed value used throughout the entire test suite.

Added.

Some of the successful solutions are actually not valid in the case of c(2); they result in c(2) = 3. We should add a test case for c(2) = 2.

I like it, most of us went with filter, reduce, loops, modulo

Nice solution with all logic in the Person class. I like it.