Definition df-s3 11453

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 11446	. 2 class <" A B C ">
5	1, 2	cs2 11445	. . 3 class <" A B ">
6	3	cs1 11307	. . 3 class <" C ">
7		cconcat 11282	. . 3 class ++
8	5, 6, 7	co 6052	. 2 class ( <" A B "> ++ <" C "> )
9	4, 8	wceq 1398	1 wff <" A B C "> = ( <" A B "> ++ <" C "> )

This definition is referenced by:  s3eqd  11467  s3cld  11475  s3fv0g  11487  s3fv1g  11488  s3fv2g  11489  s1s2d  11490  s1s3d  11491  s2s2d  11496  s4s3d  11498  s3s4d  11499  konigsberglem1  16500  konigsberglem2  16501  konigsberglem3  16502