1.0 KiB
1.0 KiB
id | title | challengeType | forumTopicId | dashedName |
---|---|---|---|---|
5900f46b1000cf542c50ff7d | Problem 254: Sums of Digit Factorials | 5 | 301902 | problem-254-sums-of-digit-factorials |
--description--
Define f(n)
as the sum of the factorials of the digits of n
. For example, f(342) = 3! + 4! + 2! = 32
.
Define sf(n)
as the sum of the digits of f(n)
. So sf(342) = 3 + 2 = 5
.
Define g(i)
to be the smallest positive integer n
such that sf(n) = i
. Though sf(342)
is 5, sf(25)
is also 5, and it can be verified that g(5)
is 25.
Define sg(i)
as the sum of the digits of g(i)
. So sg(5) = 2 + 5 = 7
.
Further, it can be verified that g(20)
is 267 and \sum sg(i)
for 1 ≤ i ≤ 20
is 156.
What is \sum sg(i)
for 1 ≤ i ≤ 150
?
--hints--
sumsOfDigitFactorials()
should return 8184523820510
.
assert.strictEqual(sumsOfDigitFactorials(), 8184523820510);
--seed--
--seed-contents--
function sumsOfDigitFactorials() {
return true;
}
sumsOfDigitFactorials();
--solutions--
// solution required