- Problem 98 - Anagramic squares
- Problem 49 - Prime permutations
- Problem 125 - Palindromic sums
- Random coordinates
- Problem 69 - Totient maximum
- Problem 87 - Prime power triplets
- Problem 58 - Spiral primes
- Longest word
- Problem 110 - Diophantine reciprocals II
- Prime factorisation
- Problem 108 - Diophantine reciprocals I
- Problem 119 - Digit power sum
- Problem 99 - Largest exponential
- Problem 52 - Permuted multiples
- Problem 45 - Triangular, pentagonal, and hexagonal