Prog Challenge

We all know the classic magic numbers, like 0xcafebabe and 0xdeadba11

But are there more? Write a routine which given an english dictionary finds all words re-presentable in hex that way.

Challenge: make it O(n)

let words = [];
foreach(let d : dict) {
if(d.all(l : '157abcdef'.contains(l)))
words.add(d)
}

o(n)