This is an inofficial mirror of http://metamath.tirix.org for personal testing of a visualizer extension only.
Metamath Proof Explorer
Description: Closure of exponentiation of nonnegative integers. (Contributed by NM, 16-Dec-2005)
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|
Ref |
Expression |
|
Assertion |
nnexpcl |
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Proof
| Step |
Hyp |
Ref |
Expression |
| 1 |
|
nnsscn |
|
| 2 |
|
nnmulcl |
|
| 3 |
|
1nn |
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| 4 |
1 2 3
|
expcllem |
|