Leyland number

Math A Leyland number is a number of the form \(x^y+y^x\), where x ≥ y > 1.

Why \((x, y)\ne1\)
This restriction was placed to make sure only some integers are used.If x or y is equal to 1, every positive integer is a Leyland number.

Why \((x\geq y\)
To ensure that there will not be repetitions, due to addition being commutative.

Example
\(4^3+3^4 = 64+81=145\) is a Leyland number.

The Leyland numbers are 8, 17, 32, 54, 57, 100, 145, 177, 320, 368, 512, 593, 945, 1124, ... (sequence A076980 in OEIS)