Theorem ltrelpi 10849

Description: Positive integer 'less than' is a relation on positive integers. (Contributed by NM, 8-Feb-1996.) (New usage is discouraged.)

Assertion

Ref	Expression
ltrelpi	⊢ <N ⊆ (N × N)

Proof of Theorem ltrelpi

Step	Hyp	Ref	Expression
1		df-lti 10835	. 2 ⊢ <N = ( E ∩ (N × N))
2		inss2 4204	. 2 ⊢ ( E ∩ (N × N)) ⊆ (N × N)
3	1, 2	eqsstri 3996	1 ⊢ <N ⊆ (N × N)

Syntax hints:   ∩ cin 3916   ⊆ wss 3917   E cep 5540   × cxp 5639  Ncnpi 10804   <_N clti 10807

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1795  ax-4 1809  ax-5 1910  ax-6 1967  ax-7 2008  ax-8 2111  ax-9 2119  ax-ext 2702

This theorem depends on definitions:  df-bi 207  df-an 396  df-tru 1543  df-ex 1780  df-sb 2066  df-clab 2709  df-cleq 2722  df-clel 2804  df-rab 3409  df-v 3452  df-in 3924  df-ss 3934  df-lti 10835

This theorem is referenced by:  ltapi  10863  ltmpi  10864  nlt1pi  10866  indpi  10867  ordpipq  10902  ltsonq  10929  archnq  10940