Tagged Questions
6
votes
2answers
360 views
Easier program for period of Fibonacci sequence modulo p
For a little project I need to calculate the period of a Fibonacci sequence modulo p, for which p is a prime number. For example, the Fibonacci sequence modulo 19 would be:
$$0, 1, 1, 2, 3, 5, 8, 13, ...
18
votes
11answers
640 views
Generating an ordered list of pairs of elements from ordered lists
I have a pair of ordered lists. I want to generate a new ordered list (using the same ordering) of length n by applying a binary operator to pairs of elements, one from each list, along with the index ...
7
votes
2answers
270 views
find subsequences of constant increase
A list like
l = {0, 1, 2, 3, 4, 5, 7, 9, 12, 13, 18, 19}
may have subsequences of constant increase, $a_{n+1} = a_n + k$.
For example:
...
4
votes
1answer
383 views
Efficient backtracking with Mathematica
Backtracking is a general algorithm for finding all (or some) solutions to some computational problem, that incrementally builds candidates to the solutions, and abandons each partial candidate c ...
27
votes
4answers
935 views
Finding a percolation path
I would like to examine percolation on a random lattice. To be exact, I wish to find the minimum length of a 'bond' needed such that the leftmost site can be connected to the rightmost site.
Here is ...
14
votes
3answers
658 views
Effective matrix power like algorithm
First example
Suppose you want to calculate the 6th power of some matrix $A$. The brute force attempt of doing this is considering
$$(((AA)A)A)A)A$$
which requires a total of 5 matrix ...
13
votes
5answers
958 views
Finding all elements within a certain range in a sorted list
Suppose we have a sorted list of values. Let's use list = Sort@RandomReal[1, 1000000]; for this example.
I need a fast function ...
15
votes
5answers
331 views
Alternative ways to implement a triangular recursion
Triangular recursions are a class of algorithms that frequently turn up in computational mathematics. These recursions are expressible in the general form
...
