Definition df-s3 12945

Description: Define the length 3 word constructor. (Contributed by Mario Carneiro, 26-Feb-2016.)

Assertion

Ref	Expression
df-s3	|- <" A B C "> = ( <" A B "> ++ <" C "> )

Detailed syntax breakdown of Definition df-s3

Step	Hyp	Ref	Expression
1		cA	. . 3 class A
2		cB	. . 3 class B
3		cC	. . 3 class C
4	1, 2, 3	cs3 12938	. 2 class <" A B C ">
5	1, 2	cs2 12937	. . 3 class <" A B ">
6	3	cs1 12661	. . 3 class <" C ">
7		cconcat 12660	. . 3 class ++
8	5, 6, 7	co 6304	. 2 class ( <" A B "> ++ <" C "> )
9	4, 8	wceq 1438	1 wff <" A B C "> = ( <" A B "> ++ <" C "> )

This definition is referenced by:  s3eqd  12959  s3cld  12966  s3cli  12975  s3fv0  12984  s3fv1  12985  s3fv2  12986  s3len  12987  s4prop  12998  s3co  13004  s1s2  13006  s1s3  13007  s2s2  13012  s4s3  13014  repsw3  13024  konigsberg  25711