Tagged Questions
1
vote
3answers
113 views
Largest prime factor of 600851475143 [duplicate]
I'm trying to use a program to find the largest prime factor of 600851475143.
This is for Project Euler here: http://projecteuler.net/problem=3
I first attempted this with the code that goes through ...
1
vote
4answers
355 views
The longest sum of consecutive primes that add to a prime less than 1,000,000
In Project Euler problem $50,$ the goal is to find the longest sum of consecutive primes that add to a prime less than $1,000,000. $
I have an efficient algorithm to generate a set of primes ...
1
vote
1answer
132 views
Algorithm for generating an ordered list of pair products
For problem 4 in the euler project part of the assignment is to generate a list of products of 3-digit numbers.
The easy way is to just do a cartesian product (I think it's called), and after that ...
2
votes
1answer
273 views
Finding all possible paths from one corner to the other on a grid, without backtracking
Me again "new to maths guy". Please tell me if the substance of my questions are not a good fit for the site.
I'm now onto Question 15 of Project Euler and it seems like there's some mathematical ...
2
votes
0answers
358 views
Counting couples having least common multiple less than a number
Let f(n) be the number of couples (x,y) with x and y positive integers, $x\leq y$ and the least common multiple of x and y equal to n.
Let g be the summatory function of f, i.e.:
$g(n) = ...
2
votes
0answers
162 views
Bell-like recurrence
Let
$$A(n)=\sum_{k=0}^{n-1}\binom{n}{k}A(k)+n!,\quad A(0)=1$$
$$B(n)=\sum_{k=0}^{n-1}\binom{n}{k}B(k)-n!-n!\sum_{k=1}^{n}\frac{1}{k!},\quad B(0)=-1.$$
I'm interested in computing $S(n)=A(n)+B(n)$ ...
0
votes
2answers
110 views
What is wrong with my algorithm (finding if the origin is within a triangle's interior)?
I am working on Project Euler Problem 102 and I thought I had a solution, but it seems I do not.
Now, don't give me the solution. I know I'm on the right track. What I want to know is why my method ...
4
votes
0answers
502 views
Project Euler Problem 338
I'm stuck on Project Euler problem 338. This is a cross post from StackOverflow where I initially posted, however, it was suggested that I post it here too since the problem mostly relies on math. The ...
