The On-Line Encyclopedia of Bongard Problems

One protrusion and one indentation of the same shape vs. not so.

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	CROSSREFS	`Adjacent-numbered pages: BP120 BP121 BP122 BP123 BP124 * BP126 BP127 BP128 BP129 BP130`
	KEYWORD	`traditional`
	CONCEPT	`indentation (info \| search),` `protrusion (info \| search),` `same_shape (info \| search),` `same (info \| search)`
	AUTHOR	`Douglas R. Hofstadter`

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