Description: Lemma 1 for 2lgsoddprmlem3 . (Contributed by AV, 20-Jul-2021)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | 2lgsoddprmlem3a | ⊢ ( ( ( 1 ↑ 2 ) − 1 ) / 8 ) = 0 | 
| Step | Hyp | Ref | Expression | 
|---|---|---|---|
| 1 | sq1 | ⊢ ( 1 ↑ 2 ) = 1 | |
| 2 | 1 | oveq1i | ⊢ ( ( 1 ↑ 2 ) − 1 ) = ( 1 − 1 ) | 
| 3 | 1m1e0 | ⊢ ( 1 − 1 ) = 0 | |
| 4 | 2 3 | eqtri | ⊢ ( ( 1 ↑ 2 ) − 1 ) = 0 | 
| 5 | 4 | oveq1i | ⊢ ( ( ( 1 ↑ 2 ) − 1 ) / 8 ) = ( 0 / 8 ) | 
| 6 | 8cn | ⊢ 8 ∈ ℂ | |
| 7 | 0re | ⊢ 0 ∈ ℝ | |
| 8 | 8pos | ⊢ 0 < 8 | |
| 9 | 7 8 | gtneii | ⊢ 8 ≠ 0 | 
| 10 | 6 9 | div0i | ⊢ ( 0 / 8 ) = 0 | 
| 11 | 5 10 | eqtri | ⊢ ( ( ( 1 ↑ 2 ) − 1 ) / 8 ) = 0 |