A sequence of letters is considered "valid" if it occurs as a substring of a common English word. For example, "RGRO" is valid because it occurs in the word "undeRGROund."

Find a sequence of four distinct letters such that all 23 non-identity permutations of the sequence are valid.

(In reply to Another one (weird but not dreigh) by Penny)

I'm sure that by "bombadier" for RDIE you meant "bombardier" ... but why not just use "birdie"? Or just "credit" instead of "accredit"? Even still, most of those are quite a stretch: "diedric," "dreigh," "preidentify," and "hyperdeify" did not appear in any dictionary I checked, while "Madeira" is a proper noun. Still, a good effort, and probably a combination I would have checked eventually as D and R are another pair of letters that go quite nicely together.

Posted by DJ on 2005-01-14 06:29:44