Layland

A Leyland number is a number of the form xʸ + yˣ where x and y are integers greater than 1. They are named after Paul Leyland. The sequence grows very quickly.

Key features

• Require x, y ≥ 2; order matters (2³ + 3² = 17 ≠ 3² + 2³ in general).
• The smallest Leyland numbers are 8, 17, 32, 54, 57.

Examples:

8, 17, 32, 54, 57

Further reading

• Layland on Wikipedia
• Layland on OEIS