Zulip Chat Archive
Stream: Is there code for X?
Topic: nat.pow_pos
Ruben Van de Velde (Sep 15 2020 at 19:14):
Is there a reason to have both of these?
theorem nat.pos_pow_of_pos {b : ℕ} (n : ℕ) : 0 < b → 0 < b ^ n
theorem nat.pow_pos {p : ℕ} (hp : 0 < p) (n : ℕ) : 0 < p ^ n
and do we not have
lemma nat.pos_pow_iff {b : ℕ} (n : ℕ) (h : 0 < n) : 0 < b ↔ 0 < b ^ n
at all?
Johan Commelin (Sep 15 2020 at 19:21):
Just historical accidents... Note that it is likely better to swap the sides of the pos_pow_iff
statement.
Feel free to PR.
Rob Lewis (Sep 15 2020 at 19:21):
0^0 = 1
, no?
Ruben Van de Velde (Sep 15 2020 at 19:22):
Hence the 0 < n
hypothesis, yeah
Rob Lewis (Sep 15 2020 at 19:23):
Oh, duh.
Last updated: Dec 20 2023 at 11:08 UTC