19 lines
550 B
Text
19 lines
550 B
Text
[ ' [ [ 1 ] ] ' [ 1 ]
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rot 1 - times
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[ dup -1 peek nested
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swap witheach
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[ over -1 peek + join ]
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tuck nested join swap ]
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drop ] is bell's-triangle ( n --> [ )
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[ bell's-triangle [] swap
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witheach [ 0 peek join ] ] is bell-numbers ( n --> [ )
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say "First fifteen Bell numbers:" cr
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15 bell-numbers echo
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cr cr
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say "Fiftieth Bell number:" cr
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50 bell-numbers -1 peek echo
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cr cr
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say "First ten rows of Bell's triangle:" cr
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10 bell's-triangle witheach [ echo cr ]
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