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Theorem 1p1e2apr1 26714
 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.)
Assertion
Ref Expression
1p1e2apr1 (1 + 1) = 2

Proof of Theorem 1p1e2apr1
StepHypRef Expression
1 df-2 10956 . 2 2 = (1 + 1)
21eqcomi 2619 1 (1 + 1) = 2
 Colors of variables: wff setvar class Syntax hints:   = wceq 1475  (class class class)co 6549  1c1 9816   + caddc 9818  2c2 10947 This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1713  ax-4 1728  ax-ext 2590 This theorem depends on definitions:  df-bi 196  df-cleq 2603  df-2 10956 This theorem is referenced by: (None)
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