Problem 49733. Solve the arithmetic differential equation D(n) = n
Cody Problem 47843 involved the arithmetic derivative of integers. In particular,
if p is prime and
. Therefore, the arithmetic derivatives of 1, 2, 3, 4, 5, and 6 are 0, 1, 1, 4, 1, and 5, respectively.
One might then ask about solving arithmetic differential equations (ADEs). Because the study of differential equations often starts with solving
, let’s consider the analogous ADE
. The definition of the arithmetic derivative shows that no prime can solve this equation, but the sample calculations above show that the first (i.e.,
) solution is 4.
Write a function to compute the mth solution to this ADE. Because the solutions become large quickly, return the logarithm of the solution.
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Prime Numbers II
- 19 Problems
- 7 Finishers
- List the delete-a-digit primes
- List the dihedral primes
- List the good primes
- Determine whether a number is a prime self number
- Compute home primes in a given base
- List Proth primes
- Label primes with the Erdos-Selfridge classification
- List Honaker primes
- List the nth prime quartet prefix
- Find the smallest prime with n inside
- List prime anagrams of a number
- Determine whether a number is unprimeable
- Count the primes in Collatz sequences
- Play Outside In with primes
- Identify prime words
- Find pairs of primes with the same digit sum and a specified separation
- List composite numbers that cannot be written as the sum of two primes
- Compute the arithmetic derivative of integers
- Solve the arithmetic differential equation D(n) = n
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