Seven friends, named Adams, Brooks, Cater, Dobson, Edwards, Fry, and Green, were spending fifteen days together at the seaside, and they had a round breakfast table at the hotel all to themselves. 

It was agreed that no man should ever sit down twice with the same two neighbours. 

As they can be seated, under these conditions, in just fifteen ways, the plan was quite practicable. 

But could the reader have prepared an arrangement for every sitting? 

The hotel proprietor was asked to draw up a scheme, but he miserably failed.

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