Metamath Proof Explorer


Definition df-frgp

Description: Define the free group on a set I of generators, defined as the quotient of the free monoid on I X. 2o (representing the generator elements and their formal inverses) by the free group equivalence relation df-efg . (Contributed by Mario Carneiro, 1-Oct-2015)

Ref Expression
Assertion df-frgp freeGrp=iVfreeMndi×2𝑜/𝑠~FGi

Detailed syntax breakdown

Step Hyp Ref Expression
0 cfrgp classfreeGrp
1 vi setvari
2 cvv classV
3 cfrmd classfreeMnd
4 1 cv setvari
5 c2o class2𝑜
6 4 5 cxp classi×2𝑜
7 6 3 cfv classfreeMndi×2𝑜
8 cqus class/𝑠
9 cefg class~FG
10 4 9 cfv class~FGi
11 7 10 8 co classfreeMndi×2𝑜/𝑠~FGi
12 1 2 11 cmpt classiVfreeMndi×2𝑜/𝑠~FGi
13 0 12 wceq wfffreeGrp=iVfreeMndi×2𝑜/𝑠~FGi