756 B
756 B
id | title | challengeType | forumTopicId | dashedName |
---|---|---|---|---|
5900f4ed1000cf542c50ffff | Problem 383: Divisibility comparison between factorials | 5 | 302047 | problem-383-divisibility-comparison-between-factorials |
--description--
Let f5(n) be the largest integer x for which 5x divides n.
For example, f5(625000) = 7.
Let T5(n) be the number of integers i which satisfy f5((2·i-1)!) < 2·f5(i!) and 1 ≤ i ≤ n. It can be verified that T5(103) = 68 and T5(109) = 2408210.
Find T5(1018).
--hints--
euler383()
should return 22173624649806.
assert.strictEqual(euler383(), 22173624649806);
--seed--
--seed-contents--
function euler383() {
return true;
}
euler383();
--solutions--
// solution required