Problem 45429. Prime Sum
What is the minimum value that can be written as sum of primes in n different ways?
For example, 10 is the minimum value that can be written as the sum of primes in exactly five different ways:
2 + 2 + 2 + 2 + 2 2 + 2 + 3 + 3 2 + 3 + 5 5 + 5 3 +7
8 can be written in 3 different ways but 7 can also be written in 3 different ways. So 7 is the right answer.
Solution Stats
Problem Comments
-
3 Comments
what are the three ways to obtain 7 by summing primes?! 2+5, 2+2+3, and?
Found at a blog that if a number is prime, wrongly some people consider this a sum. So the third way to obtain 7 would be 7 by itself, which is wrong, because it should actually be 7+0, but 0 is not a prime (and 7 by itself is not a sum). https://medium.com/@yevgeniy.v.filatov/counting-the-ways-to-express-a-number-as-a-sum-of-primes-e5e871b48193#:~:text=For%20the%20number%207%20we,as%20a%20sum%20of%20primes.
Maybe it's more precise to say partitions instead of a sum. In any case, solving CP 1240 helps here as well.
Solution Comments
Show commentsProblem Recent Solvers7
Suggested Problems
-
Make the vector [1 2 3 4 5 6 7 8 9 10]
49534 Solvers
-
1658 Solvers
-
1226 Solvers
-
479 Solvers
-
Is my wife right? Now with even more wrong husband
1322 Solvers
More from this Author165
Problem Tags
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!