Let be the number of positive divisors of . Let be the number of positive divisors of which have remainders when divided by . Find all positive integral values of the fraction .
Solution
Given the problem with representing the number of positive divisors of , and representing the number of positive divisors of that leave a remainder of 1 when divided by 3, we are tasked to find all positive integral values of the fraction .
### Step 1: Analyze
The number has the prime factorization . The formula to find the total number of divisors is to add 1 to each of the exponents in the prime factorization and take their product. Therefore, if has a prime factorization , then the prime factorization of is .
Thus, the number of divisors of , i.e., , is:
where the product is over all other primes dividing .
### Step 2: Analyze
A divisor of is in if . For divisors modulo 3:
- and satisfies.
- and doesn't satisfy.
- doesn't satisfy.
- satisfies.
- and doesn't satisfy.
- and doesn't satisfy.
- satisfies.
- And so forth ...
### Step 3: Compute
From the above logic, only those divisors that are congruent to count towards . Calculation can become cumbersome without specific values for divisors. However, one key aspect is that if is a composite number such that higher configurations of divisors modulo 3 are satisfied more (except when modulo is directly involved), the fraction tends to have more integer solutions. Importantly, observe that with these divisors:
- Perfect configurations (like multiples having both every and others altogether) typically have integer outputs.
Potential integer solutions for , based on problem structuring, are derived across composite given certain value structures or even dividing ratios cleanly:
- The simplest key is indeed in larger numbers as remainders actualize meaningful \mod patterns of non-perfect divisors or extra composites that sometimes can become consistent divisors to more integral form gains.
Thus, the values match the composite numbers together, sensibly with .
Therefore, all possible positive integral results for the fraction are: