Suppose there is a number k, then f(k) is the sum of all perfect powers that divides k. For a given N We need to find f(1) + f(2) + .... f(N). N can be upto 10^18.
My solution is naive and cannot work for bigger N. Can someone suggest some formula for solving the problem.
I wondered whether MO has at any point formulated some policy on questions from ongoing contest.
Maybe one could say that they are likely to be closed - since typically such questions are not research-level. But in my experience, many non-research-level questions are left open on MO.
What is our policy concerning contest questions on the Mathematics Stack Exchange?
Why do we have a policy?
What is a contest question?
How we deal with on-going contest questions?
I see a question that I know is from a contest, what do I do?
What is our policy concerning contest questions on the Mathematics Stack Exchange?
Why do we have a policy?
What is a contest question?
How we deal with on-going contest questions?
I see a question that I know is from a contest, what do I do?
