Linked Questions

2
votes
4answers
3k views

find the number of integral solutions a+b+c+d+e+f = 18 [duplicate]

Find the number of integral solutions of a + b + c + d + e + f = 18 where a, b, c, d, e, f are elements of the range ...
1
vote
2answers
405 views

Solving an equation for all possible integer solutions [duplicate]

Problem: A person spends 15 dollars at the store. Eggs cost 1 dollar. Milk costs 2 dollars and bread costs 3 dollars. I'm attempting to create a list of all possible integer solutions to the problem. ...
14
votes
2answers
640 views

Is there a way to use functions like Prime[n] within Solve[]?

I'm trying to see if a number can be written as the sum of two prime numbers. Ideally, I would like to use Solve[ Prime[n] + Prime[m] == 100, {n, m}] But that ...
10
votes
3answers
1k views

How do I make Reduce yield all solutions explicitly?

Say I want to do the following: Reduce[ x+y+z==1, {x,y,z}, Modulus -> 7 ] then I get a solution with parameters, C[1] : <...
6
votes
3answers
590 views

How to count the integer grid numbers defined by inequalities?

I have the following code to show a red area defined by inequalities: ...
5
votes
3answers
645 views

removing list containing zeros

I have a list of lists which looks something like this- {{12,1,23,.....,4},{0,0,0,.....,0},{34,67,5,.....,60},{0,0,0,.....,0}}. I want list to look something like - ...
6
votes
1answer
1k views

Reduce an equation by putting a new variable

I have the following equation given: $$ (26-x)\cdot\sqrt{5x-1} -(13x+14)\cdot\sqrt{5-2x} + 12\sqrt{(5x-1)\cdot(5-2x) }= 18x+32. $$ In order to solve it, I want to substitute $t = \sqrt{5x - 1}-\sqrt{...
2
votes
2answers
942 views

How can I select elements that are true

I have a list of lists. For example, list = {{0,1,0,1,true},{0,0,0,0,false},{0,1,1,1,true},{1,1,1,1,false},{2,2,2,2,false}} I'd like to find all lists that ...
1
vote
0answers
2k views

Solve[] unexpectedly giving empty solution sets for extremely large problems

I was calculating the set of lattice vectors in $\mathbb{Z}^4$ which have taxicab norm $r$. For example, executing ...
4
votes
1answer
261 views

Finding the largest integer that cannot be partitioned in a certain way

I want to use Mathematica to solve the problem: Find the maximum $k$ such that $6x+9y+20z=k$ does not have a non-negative solution. I tried FrobeniusSolve. But ...
1
vote
1answer
34 views

No of integral solutions with restrictions [closed]

x+y+z+w=n,where x<=w,y<=w. total number of non negative integral solutions of this equation?is there any closed form formula. what is the generalized formula across any number of variables?
2
votes
0answers
65 views

speeding up Solve(ing) the Diophantine equation

Trying to solve the Diophantine equation (or variation?) using Solve in order to generate some chemical formulas. I need to generate all possible solutions. The ...