Theorem bj-el2oss1o 14797

Description: Shorter proof of el2oss1o 6457 using more axioms. (Contributed by BJ, 21-Jan-2024.) (Proof modification is discouraged.) (New usage is discouraged.)

Assertion

Ref	Expression
bj-el2oss1o	|- ( A e. 2o -> A C_ 1o )

Proof of Theorem bj-el2oss1o

Step	Hyp	Ref	Expression
1		1on 6437	. . . 4 |- 1o e. On
2	1	ontrci 4439	. . 3 |- Tr 1o
3		trsucss 4435	. . 3 |- ( Tr 1o -> ( A e. suc 1o -> A C_ 1o ) )
4	2, 3	ax-mp 5	. 2 |- ( A e. suc 1o -> A C_ 1o )
5		df-2o 6431	. 2 |- 2o = suc 1o
6	4, 5	eleq2s 2282	1 |- ( A e. 2o -> A C_ 1o )

Syntax hints:   -> wi 4   e. wcel 2158   C_ wss 3141   Tr wtr 4113   suc csuc 4377   1oc1o 6423   2oc2o 6424

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 106  ax-ia2 107  ax-ia3 108  ax-in1 615  ax-in2 616  ax-io 710  ax-5 1457  ax-7 1458  ax-gen 1459  ax-ie1 1503  ax-ie2 1504  ax-8 1514  ax-10 1515  ax-11 1516  ax-i12 1517  ax-bndl 1519  ax-4 1520  ax-17 1536  ax-i9 1540  ax-ial 1544  ax-i5r 1545  ax-13 2160  ax-14 2161  ax-ext 2169  ax-sep 4133  ax-nul 4141  ax-pow 4186  ax-pr 4221  ax-un 4445

This theorem depends on definitions:  df-bi 117  df-tru 1366  df-nf 1471  df-sb 1773  df-clab 2174  df-cleq 2180  df-clel 2183  df-nfc 2318  df-ral 2470  df-rex 2471  df-v 2751  df-dif 3143  df-un 3145  df-in 3147  df-ss 3154  df-nul 3435  df-pw 3589  df-sn 3610  df-pr 3611  df-uni 3822  df-tr 4114  df-iord 4378  df-on 4380  df-suc 4383  df-1o 6430  df-2o 6431

This theorem is referenced by: (None)