できた
JavaScript
const prodPrimes = n => {
const primes = [1];
for (let m = n; m > 1; m--) {
let prime = 0;
for (let i = 2; i <= m - 1; i++) {
if (m % i === 0) prime = i;
}
primes.push(prime || m);
}
return [...new Set(primes)].reduce((acc, p) => acc * p);
}
console.log(prodPrimes(1)); //=> 1
console.log(prodPrimes(3)); //=> 6
console.log(prodPrimes(4)); //=> 6
console.log(prodPrimes(5)); //=> 30

今夜はPythonで>>316に挑戦したい