Description: A nonnegative integer increased by 1 is greater than 0. (Contributed by Alexander van der Vekens, 3-Oct-2018)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | nn0p1gt0 | |- ( N e. NN0 -> 0 < ( N + 1 ) ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | nn0re | |- ( N e. NN0 -> N e. RR ) |
|
| 2 | 1red | |- ( N e. NN0 -> 1 e. RR ) |
|
| 3 | nn0ge0 | |- ( N e. NN0 -> 0 <_ N ) |
|
| 4 | 0lt1 | |- 0 < 1 |
|
| 5 | 4 | a1i | |- ( N e. NN0 -> 0 < 1 ) |
| 6 | 1 2 3 5 | addgegt0d | |- ( N e. NN0 -> 0 < ( N + 1 ) ) |