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bio website uclue.com
location Knoxville, TN
age 61
visits member for 2 years, 3 months
seen 18 hours ago

Enjoys programming in Prolog.


Mar
25
comment Fibonacci, variation on the theme
I suspect we don't need to store a lot of $a(p)$ values to get a benefit in sieving, but you've done more computations than I have. How does the number of solutions between $10^N$ and $10^{N+1}$ seem to behave as $N$ grows?
Mar
22
revised Fibonacci, variation on the theme
Added links, some details of sieving procedure, notion of "primitive" solutions
Mar
22
answered Fibonacci, variation on the theme
Mar
20
comment Fibonacci, variation on the theme
That's a valid doubt. It suggests one might benefit by doing some Fibonacci steps of modest prime lengths to sieve out the bulk of numbers to be tested.
Mar
13
comment Fibonacci, variation on the theme
It looks like the computation of Fibonacci number $F_n$ is done from scratch with each call to fibmod. So if instead you kept two variables holding $F_{n-1}$ and $F_n$, then each iteration would only require an addition and a reduction mod $n$, with a bit of shuffling of values to keep the last two Fibonacci numbers for the next iteration.
Mar
9
reviewed Reviewed Solving a non linear equation and iterating for various values in python
Mar
9
comment Solving a non linear equation and iterating for various values in python
As a practical matter, how would one know how many solutions to expect? Some thoughtful analysis is usually required even for the case of a real polynomial, in that the number of real solutions may be less than the degree (even setting aside issues of multiplicity of roots). In a wider setting there could be infinitely many solutions for one unknown in one equation.
Feb
10
reviewed Reject suggested edit on Integration of an indefinite integral: matlab precision problem
Feb
2
reviewed Close polynomiality of a problem
Feb
2
reviewed Leave Open Nonconvex Optimization
Feb
2
comment Nonconvex Optimization
In its current form the variable $x$ seems to have no connection to the optimization problem.
Jan
27
comment Algorithm to find non-negative integer solutions to x_1 + x_2 …=n
There are a number of neat algorithmic ideas out there for generating weak compositions with $k$-parts, as you wish to do. I'll try to summarize things related to your clarifications (commented above), but in the meantime there's a dissertation (2005) that gives a good summary of recent literature.
Jan
24
comment Algorithm to find non-negative integer solutions to x_1 + x_2 …=n
It seems doubtful that one can realize an $O(1)$ complexity, in view of the fact we are outputting something of size $k$ (the solution), but something along these lines might be useful in generating "random" solutions.
Jan
24
reviewed Excellent Finite element discretization of Reaction-diffusion problem with Dirac source term
Jan
24
reviewed Excellent Is there congruent transform implementation for dense symmetric matrix in Eigen(C++)?
Jan
24
reviewed Excellent Slow convergence of Newton's method for finite elements
Jan
24
reviewed Excellent Methods to solve this equation on finite fields?
Jan
24
reviewed Satisfactory Best place to start learning Stereophotogrammetry
Jan
24
reviewed Excellent Solve chemical formula (number of molecules in reaction)
Jan
24
reviewed Satisfactory Partial derivatives of a 3D array in Matlab