Definition df-wsuc 35245

Description: Define the concept of a successor in a well-founded set. (Contributed by Scott Fenton, 13-Jun-2018.) (Revised by AV, 10-Oct-2021.)

Assertion

Ref	Expression
df-wsuc	⊢ wsuc(𝑅, 𝐴, 𝑋) = inf(Pred(◡𝑅, 𝐴, 𝑋), 𝐴, 𝑅)

Detailed syntax breakdown of Definition df-wsuc

Step	Hyp	Ref	Expression
1		cA	. . 3 class 𝐴
2		cR	. . 3 class 𝑅
3		cX	. . 3 class 𝑋
4	1, 2, 3	cwsuc 35243	. 2 class wsuc(𝑅, 𝐴, 𝑋)
5	2	ccnv 5665	. . . 4 class ◡𝑅
6	1, 5, 3	cpred 6289	. . 3 class Pred(◡𝑅, 𝐴, 𝑋)
7	6, 1, 2	cinf 9431	. 2 class inf(Pred(◡𝑅, 𝐴, 𝑋), 𝐴, 𝑅)
8	4, 7	wceq 1533	1 wff wsuc(𝑅, 𝐴, 𝑋) = inf(Pred(◡𝑅, 𝐴, 𝑋), 𝐴, 𝑅)

This definition is referenced by:  wsuceq123  35247  nfwsuc  35251  wsucex  35259  wsuccl  35260  wsuclb  35261