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| Mirrors > Home > MPE Home > Th. List > 1p1e2apr1 | Structured version Visualization version GIF version | ||
| Description: One plus one equals two. Using proof-shortening techniques pioneered by Mr. Mel L. O'Cat, along with the latest supercomputer technology, Prof. Loof Lirpa and colleagues were able to shorten Whitehead and Russell's 360-page proof that 1+1=2 in Principia Mathematica to this remarkable proof only two steps long, thus establishing a new world's record for this famous theorem. (Contributed by Prof. Loof Lirpa, 1-Apr-2008.) (Proof modification is discouraged.) (New usage is discouraged.) |
| Ref | Expression |
|---|---|
| 1p1e2apr1 | ⊢ (1 + 1) = 2 |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | df-2 12308 | . 2 ⊢ 2 = (1 + 1) | |
| 2 | 1 | eqcomi 2745 | 1 ⊢ (1 + 1) = 2 |
| Colors of variables: wff setvar class |
| Syntax hints: = wceq 1540 (class class class)co 7410 1c1 11135 + caddc 11137 2c2 12300 |
| This theorem was proved from axioms: ax-mp 5 ax-1 6 ax-2 7 ax-3 8 ax-gen 1795 ax-4 1809 ax-5 1910 ax-6 1967 ax-7 2008 ax-9 2119 ax-ext 2708 |
| This theorem depends on definitions: df-bi 207 df-an 396 df-ex 1780 df-cleq 2728 df-2 12308 |
| This theorem is referenced by: (None) |
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