Theorem b0ne0 | index | src |

theorem b0ne0 (n: nat): $ b0 n != 0 <-> n != 0 $;
StepHypRefExpression
1 bitr3
(2 * n != 0 <-> b0 n != 0) -> (2 * n != 0 <-> n != 0) -> (b0 n != 0 <-> n != 0)
2 neeq1
2 * n = b0 n -> (2 * n != 0 <-> b0 n != 0)
3 b0mul21
2 * n = b0 n
4 2, 3 ax_mp
2 * n != 0 <-> b0 n != 0
5 1, 4 ax_mp
(2 * n != 0 <-> n != 0) -> (b0 n != 0 <-> n != 0)
6 bitr
(2 * n != 0 <-> 2 != 0 /\ n != 0) -> (2 != 0 /\ n != 0 <-> n != 0) -> (2 * n != 0 <-> n != 0)
7 mulne0
2 * n != 0 <-> 2 != 0 /\ n != 0
8 6, 7 ax_mp
(2 != 0 /\ n != 0 <-> n != 0) -> (2 * n != 0 <-> n != 0)
9 bian1
2 != 0 -> (2 != 0 /\ n != 0 <-> n != 0)
10 d2ne0
2 != 0
11 9, 10 ax_mp
2 != 0 /\ n != 0 <-> n != 0
12 8, 11 ax_mp
2 * n != 0 <-> n != 0
13 5, 12 ax_mp
b0 n != 0 <-> n != 0

Axiom use

axs_prop_calc (ax_1, ax_2, ax_3, ax_mp, itru), axs_pred_calc (ax_gen, ax_4, ax_5, ax_6, ax_7, ax_10, ax_11, ax_12), axs_peano (peano1, peano2, peano5, addeq, muleq, add0, addS, mul0, mulS)