Definition df-s3 11550

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 11543	. 2 class <" A B C ">
5	1, 2	cs2 11542	. . 3 class <" A B ">
6	3	cs1 11404	. . 3 class <" C ">
7		cconcat 11379	. . 3 class ++
8	5, 6, 7	co 6088	. 2 class ( <" A B "> ++ <" C "> )
9	4, 8	wceq 1402	1 wff <" A B C "> = ( <" A B "> ++ <" C "> )

This definition is used by:  s3eqd  11564  s3cld  11572  s3fv0g  11584  s3fv1g  11585  s3fv2g  11586  s1s2d  11587  s1s3d  11588  s2s2d  11593  s4s3d  11595  s3s4d  11596  konigsberglem1  16951  konigsberglem2  16952  konigsberglem3  16953