Metamath Proof Explorer


Theorem oppglemOLD

Description: Obsolete version of setsplusg as of 18-Oct-2024. Lemma for oppgbas . (Contributed by Stefan O'Rear, 26-Aug-2015) (Proof modification is discouraged.) (New usage is discouraged.)

Ref Expression
Hypotheses oppgbas.1 O = opp 𝑔 R
oppglemOLD.2 E = Slot N
oppglemOLD.3 N
oppglemOLD.4 N 2
Assertion oppglemOLD E R = E O

Proof

Step Hyp Ref Expression
1 oppgbas.1 O = opp 𝑔 R
2 oppglemOLD.2 E = Slot N
3 oppglemOLD.3 N
4 oppglemOLD.4 N 2
5 2 3 ndxid E = Slot E ndx
6 2 3 ndxarg E ndx = N
7 plusgndx + ndx = 2
8 6 7 neeq12i E ndx + ndx N 2
9 4 8 mpbir E ndx + ndx
10 5 9 setsnid E R = E R sSet + ndx tpos + R
11 eqid + R = + R
12 11 1 oppgval O = R sSet + ndx tpos + R
13 12 fveq2i E O = E R sSet + ndx tpos + R
14 10 13 eqtr4i E R = E O