1.1 KiB
1.1 KiB
id, title, challengeType, forumTopicId
| id | title | challengeType | forumTopicId |
|---|---|---|---|
| 5900f4331000cf542c50ff45 | Problem 198: Ambiguous Numbers | 5 | 301836 |
--description--
A best approximation to a real number x for the denominator bound d is a rational number r/s (in reduced form) with s ≤ d, so that any rational number p/q which is closer to x than r/s has q > d.
Usually the best approximation to a real number is uniquely determined for all denominator bounds. However, there are some exceptions, e.g. 9/40 has the two best approximations 1/4 and 1/5 for the denominator bound 6. We shall call a real number x ambiguous, if there is at least one denominator bound for which x possesses two best approximations. Clearly, an ambiguous number is necessarily rational.
How many ambiguous numbers x = p/q, 0 < x < 1/100, are there whose denominator q does not exceed 108?
--hints--
euler198() should return 52374425.
assert.strictEqual(euler198(), 52374425);
--seed--
--seed-contents--
function euler198() {
return true;
}
euler198();
--solutions--
// solution required