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Any math wizards out there want to give us the answer.It's Sunday morning, I'm not even going to think about that kind of math - even if I had the skills to do it

Myself, I'm betting there are a whole lot of them

enough to keep this game going for years.
This person seems to think that there could be around 450,000 four letter words in the English language. Quote:
"
there are 456,976 four letter combinations (if you ignore capitalization). Among those are some groups of almost entirely nonsensical words; are quadruple letters (aaaa or zzzz) 676 single/triple (abbb, dbbb, or yzzz) 676 double/double(ttrr or gghh) and another 676 triple/single (bbba, bbbd, or zzzy) that's 2054 total letter combinations which if you only worry about spelling and not meaning takes away approximately 2054 words (there may be quadruple, single/triple, double, double, or triple/single letter words I am over looking but if there are a couple in these categories than they can be made up by the inevitable nonsensical single/single/single/single or single/single /double words) leaving 454,922 though there are probably still many 4 letter combinations I could rule out - I can safely say there are not more than 454,922 four letter words."
http://www.answerbag.com/....php/69716I've no clue if this person is correct or not. Heck, no one can even come up with a reasonable guess on how many total words there are in the English language:
How Many Words?: How many in the language and how many
does any one person know?
http://www.worldwidewords...owmany.htmHow many words are there in the English language?
http://www.askoxford.com/...umberwordsThe most 10 most frequently used letters in the English language (in order of frequency) are E T A O I N S H R D. Maybe the way to make a game like this challenging and place some limits on it, would be to ban the use of the three most frequently used letters:
E T A.
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gold -> fold