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visits | member for | 5 years, 8 months |
seen | Jul 1 '10 at 23:42 | |
stats | profile views | 90 |
Aug
6 |
awarded | Famous Question |
Jan
5 |
awarded | Notable Question |
May
31 |
awarded | Notable Question |
Dec
6 |
awarded | Notable Question |
Nov
27 |
awarded | Popular Question |
Mar
30 |
awarded | Good Question |
Feb
27 |
awarded | Popular Question |
Aug
24 |
awarded | Popular Question |
Jun
29 |
awarded | Commentator |
Jun
29 |
comment |
What is the shortest program for which halting is unknown?
Also, there's the question of how long the bit representation is of the smallest n not known to halt. |
Jun
29 |
comment |
What is the shortest program for which halting is unknown?
I guess you mean to make the function recursive? f(n) = f(n/2), f(n) = f(3n+1), etc. Also you need the base case. Otherwise this function is easily computable. :-) |
Jun
18 |
accepted | “Industry”/Government jobs for mathematicians |
Jun
17 |
awarded | Nice Question |
Jun
17 |
comment |
“Industry”/Government jobs for mathematicians
I agree that it seems there is little opportunity to publish outside of Academia -- this is why it is hard to learn what is done there. But I suppose that publishing is not a necessary condition for satisfying work, so long as there is a good internal community of mathematicians with whom to work. |
Jun
17 |
comment |
“Industry”/Government jobs for mathematicians
Hi Ian, You are right. I am a US citizen, and so am interested also in opportunities only available to US citizens; of course other opportunities are also welcome, and it makes sense to distinguish the two types. |
Jun
17 |
asked | “Industry”/Government jobs for mathematicians |
Mar
7 |
asked | Geometric interpretation of singular values |
Feb
18 |
accepted | Interesting applications of max-flow and linear programming |
Feb
17 |
asked | Interesting applications of max-flow and linear programming |
Jan
12 |
comment |
Good algorithm for finding the diameter of a (sparse) graph?
Djikstra's algorithm does not work for negative edge weights; for this, you need Bellman Ford, which runs in time O(|V||E|) = O(|V|^3) for dense graphs. The best algorithm for the all-pairs shortest paths is Floyd-Warshall, which also runs in time O(|V|^3). Note that Johnson's algorithm is faster only on sparse graphs. |