Metamath Proof Explorer


Theorem nic-axALT

Description: A direct proof of nic-ax . (Contributed by NM, 11-Dec-2008) (Proof modification is discouraged.) (New usage is discouraged.)

Ref Expression
Assertion nic-axALT φχψτττθχφθφθ

Proof

Step Hyp Ref Expression
1 simpl χψχ
2 1 imim2i φχψφχ
3 con3 φχ¬χ¬φ
4 3 imim2d φχθ¬χθ¬φ
5 2 4 syl φχψθ¬χθ¬φ
6 anidm τττ
7 6 biimpri τττ
8 5 7 jctil φχψτττθ¬χθ¬φ
9 df-nan χψ¬χψ
10 9 anbi2i φχψφ¬χψ
11 10 notbii ¬φχψ¬φ¬χψ
12 df-nan φχψ¬φχψ
13 iman φχψ¬φ¬χψ
14 11 12 13 3bitr4i φχψφχψ
15 df-nan τττθχφθφθ¬τττθχφθφθ
16 df-nan ττ¬ττ
17 16 anbi2i ττττ¬ττ
18 17 notbii ¬τττ¬τ¬ττ
19 df-nan τττ¬τττ
20 iman τττ¬τ¬ττ
21 18 19 20 3bitr4i ττττττ
22 df-nan θχ¬θχ
23 imnan θ¬χ¬θχ
24 22 23 bitr4i θχθ¬χ
25 df-nan φθφθ¬φθφθ
26 anidm φθφθφθ
27 df-nan φθ¬φθ
28 imnan φ¬θ¬φθ
29 con2b φ¬θθ¬φ
30 28 29 bitr3i ¬φθθ¬φ
31 26 27 30 3bitri φθφθθ¬φ
32 25 31 xchbinx φθφθ¬θ¬φ
33 24 32 anbi12i θχφθφθθ¬χ¬θ¬φ
34 33 notbii ¬θχφθφθ¬θ¬χ¬θ¬φ
35 df-nan θχφθφθ¬θχφθφθ
36 iman θ¬χθ¬φ¬θ¬χ¬θ¬φ
37 34 35 36 3bitr4i θχφθφθθ¬χθ¬φ
38 21 37 anbi12i τττθχφθφθτττθ¬χθ¬φ
39 15 38 xchbinx τττθχφθφθ¬τττθ¬χθ¬φ
40 14 39 anbi12i φχψτττθχφθφθφχψ¬τττθ¬χθ¬φ
41 40 notbii ¬φχψτττθχφθφθ¬φχψ¬τττθ¬χθ¬φ
42 iman φχψτττθ¬χθ¬φ¬φχψ¬τττθ¬χθ¬φ
43 41 42 bitr4i ¬φχψτττθχφθφθφχψτττθ¬χθ¬φ
44 8 43 mpbir ¬φχψτττθχφθφθ
45 df-nan φχψτττθχφθφθ¬φχψτττθχφθφθ
46 44 45 mpbir φχψτττθχφθφθ