--- id: 5949b579404977fbaefcd736 title: 9 billion names of God the integer challengeType: 5 forumTopicId: 302219 dashedName: 9-billion-names-of-god-the-integer --- # --description-- This task is a variation of the [short story by Arthur C. Clarke](https://en.wikipedia.org/wiki/The Nine Billion Names of God#Plot_summary "wp: The Nine Billion Names of God#Plot_summary"). (Solvers should be aware of the consequences of completing this task.) In detail, to specify what is meant by a "name": This can be visualized in the following form:
          1
        1   1
      1   1   1
    1   2   1   1
  1   2   2   1   1
1   3   3   2   1   1
Where row $n$ corresponds to integer $n$, and each column $C$ in row $m$ from left to right corresponds to the number of names beginning with $C$. Optionally note that the sum of the $n$-th row $P(n)$ is the integer partition function. # --instructions-- Implement a function that returns the sum of the $n$-th row. # --hints-- `numberOfNames` should be function. ```js assert(typeof numberOfNames === 'function'); ``` `numberOfNames(5)` should equal 7. ```js assert.equal(numberOfNames(5), 7); ``` `numberOfNames(12)` should equal 77. ```js assert.equal(numberOfNames(12), 77); ``` `numberOfNames(18)` should equal 385. ```js assert.equal(numberOfNames(18), 385); ``` `numberOfNames(23)` should equal 1255. ```js assert.equal(numberOfNames(23), 1255); ``` `numberOfNames(42)` should equal 53174. ```js assert.equal(numberOfNames(42), 53174); ``` `numberOfNames(123)` should equal 2552338241. ```js assert.equal(numberOfNames(123), 2552338241); ``` # --seed-- ## --seed-contents-- ```js function numberOfNames(num) { return true; } ``` # --solutions-- ```js function numberOfNames(num) { const cache = [ [1] ]; for (let l = cache.length; l < num + 1; l++) { let Aa; let Mi; const r = [0]; for (let x = 1; x < l + 1; x++) { r.push(r[r.length - 1] + (Aa = cache[l - x < 0 ? cache.length - (l - x) : l - x])[(Mi = Math.min(x, l - x)) < 0 ? Aa.length - Mi : Mi]); } cache.push(r); } return cache[num][cache[num].length - 1]; } ```