# Project Euler Problems

### What is Project Euler?

Project Euler is a series of challenging mathematical/computer programming problems that will require more than just mathematical insights to solve. Although mathematics will help you arrive at elegant and efficient methods, the use of a computer and programming skills will be required to solve most problems.

Below is a consolidated list of my attempts to solve various problems found at Project Euler.  Unless otherwise noted, each of the solutions were discovered on my own.  As with any programming assignment, there are other (possibly more efficient) ways to solve the problem, but the one presented was the one I stumbled upon first that worked.

I strongly urge you not to cheat. That defeats the purpose. Research, and if you get stuck, take a break, then research some more. You may find the answer indirectly by researching the problem (like I did with Problem 26)

Click “Attempt” to be taken to the page detailing the attempt for that problem.  If there is no link, I either haven’t posted the solution yet, or I have yet to find a solution.

1. Attempt Prime digit replacements
2. Attempt Permuted multiples
3. Attempt Combinatoric selections
4. Attempt Poker hands
5. Attempt Lychrel numbers
6. Attempt Powerful digit sum
7. Attempt Square root convergents
8. Attempt Spiral primes
9. Attempt XOR decryption
10. Attempt – Prime pair sets
11. Attempt – Cyclical figurate numbers
12. Attempt – Cubic permutations
13. Attempt – Powerful digit counts
14. Attempt – Odd period square roots
15. Attempt – Convergents of e
16. Attempt – Diophantine equation
17. Attempt Maximum path sum II
18. Attempt – Magic 5-gon ring
19. Attempt – Totient maximum
20. Attempt – Totient permutation
21. Attempt – Ordered fractions
22. Attempt – Counting fractions
23. Attempt – Counting fractions in a range
24. Attempt – Digit factorial chains
25. Attempt – Singular integer right trangles
26. Attempt – Counting summations
27. Attempt – Prime summations
28. Attempt – Coin partitions
29. Attempt – Passcode derivation
30. Attempt Square root digital expansion
31. Attempt Path sum: two ways
32. Attempt – Path sum: three ways
33. Attempt – Path sum: four ways
34. Attempt – Monopoly odds
35. Attempt – Counting rectangles
36. Attempt – Cuboid route
37. Attempt – Prime power triples
38. Attempt – Product-sum numbers
39. Attempt – Roman numerals
40. Attempt – Cube digit pairs
41. Attempt – Right triangles with integer coordinates
42. Attempt – Square digit chains
43. Attempt – Arithmetic expressions
44. Attempt – Almost equilateral triangles
45. Attempt – Amicable chains
46. Attempt – Su Doku
47. Attempt – Large non-Mersenne prime
48. Attempt – Anagramic squares
49. Attempt – Largest exponential
50. Attempt – Arranged probability