raetsel.js

'use strict';

let i = 2;
let done = false;

while (!done) {
    console.log("Checking " + i);
    const i3 = i.toString(3);
    const i4 = i.toString(4);
    const i5 = i.toString(5);

    if (hasOnly01(i3) && hasOnly01(i4) && hasOnly01(i5)) {
        const i2 = i.toString(2);
        console.log("Yay!");
        console.log(i2 + ", " + i3 + ", " + i4 + ", " + i5);
        done = true;
    }
    ++i;
}

function hasOnly01(s) {
    for (let i = 0; i < s.length; ++i) {
        if (s[i] != '0' && s[i] != '1')
            return false;
    }
    return true;
}