RosettaCodeData/Task/Perfect-numbers/JavaScript/perfect-numbers-4.js

24 lines
499 B
JavaScript

(function (nFrom, nTo) {
function perfect(n) {
var lows = range(1, Math.floor(Math.sqrt(n))).filter(function (x) {
return (n % x) === 0;
});
return n > 1 && lows.concat(lows.map(function (x) {
return n / x;
})).reduce(function (a, x) {
return a + x;
}, 0) / 2 === n;
}
function range(m, n) {
return Array.apply(null, Array(n - m + 1)).map(function (x, i) {
return m + i;
});
}
return range(nFrom, nTo).filter(perfect)
})(1, 10000);