The On-Line Encyclopedia of Bongard Problems

If any non-nosed faces exist, they are happy if and only if happy nosed faces exist as well vs. not so.

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	CROSSREFS	`Adjacent-numbered pages: BP285 BP286 BP287 BP288 BP289 * BP291 BP292 BP293 BP294 BP295`
	KEYWORD	`convoluted`
	CONCEPT	`existence (info \| search),` `iff (info \| search)`
	AUTHOR	`"Lewis"`

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