|
|
|
|
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| 1 is a number |
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| 1
isn’t the successor of a number |
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| The
successor of any number is a number |
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| No
two numbers have the same successor |
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| If a
set contains 1, and if the successor of any member of the set also |
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| belongs
to the set, then every number belongs to the set. |
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