How does Filter come up with the Junzi number in a set of numbers?

for example, if there is a set of numbers such as 1, 2, 5, 7, 11, 14, how can Filter come up with two sets of numbers: [1, 2] and [5, 6, 7, 7]?
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Mar.05,2021

is this all right?

  

result correction.

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