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BP1146 Same number of dots in top row as in leftmost column vs not so.
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This is a difficult-to-read attempt at making a Bongard Problem about perfect numbers. Grouping columns together to make rectangular arrays, each maximal (most dots possible) rectangular array of a particular height in any given example has the same number of dots in it (a perfect number, in left-sorted cases), and the dot-width of each array represents a particular divisor of that number.


It is not currently known whether there are a finite amount of examples that would be sorted left.


Every example in this Bongard Problem corresponds to a distinct natural number. There is not a way of representing the number 1 using the rules of construction for examples in this problem (if the problem were simply "Perfect number of dots vs. other number of dots", the example with 1 dot would be sorted right).

REFERENCE

https://en.wikipedia.org/wiki/Perfect_number

CROSSREFS

Adjacent-numbered pages:
BP1141 BP1142 BP1143 BP1144 BP1145  *  BP1147 BP1148 BP1149 BP1150 BP1151

KEYWORD

overriddensolution, left-listable

AUTHOR

Leo Crabbe

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