We will prove metric_on R R_bounded_metric ∀seq : set, sequence_on seq Rcauchy_sequence R R_bounded_metric seq∃x : set, converges_to R (metric_topology R R_bounded_metric) seq x.
Apply andI to the current goal.
An exact proof term for the current goal is R_bounded_metric_is_metric_on.
Let seq be given.
Assume Hseq: sequence_on seq R.
Assume Hc: cauchy_sequence R R_bounded_metric seq.
We prove the intermediate claim HabsTail: ∀eps0 : set, eps0 RRlt 0 eps0Rlt eps0 1∃N : set, N ω ∀m n : set, m ωn ωN mN nabs_SNo (add_SNo (apply_fun seq m) (minus_SNo (apply_fun seq n))) < eps0.
Let eps0 be given.
Assume Heps0R: eps0 R.
Assume Heps0Pos: Rlt 0 eps0.
Assume Heps0Lt1: Rlt eps0 1.
An exact proof term for the current goal is (cauchy_R_bounded_metric_abs_tail seq eps0 Hc Heps0R Heps0Pos Heps0Lt1).
We prove the intermediate claim HabC: ∀eps0 : set, eps0 R Rlt 0 eps0∃N : set, N ω ∀m n : set, m ωn ωN mN nabs_SNo (add_SNo (apply_fun seq m) (minus_SNo (apply_fun seq n))) < eps0.
Let eps0 be given.
Assume Heps0: eps0 R Rlt 0 eps0.
We prove the intermediate claim Heps0R: eps0 R.
An exact proof term for the current goal is (andEL (eps0 R) (Rlt 0 eps0) Heps0).
We prove the intermediate claim Heps0Pos: Rlt 0 eps0.
An exact proof term for the current goal is (andER (eps0 R) (Rlt 0 eps0) Heps0).
We prove the intermediate claim Hexd: ∃d : set, d R Rlt 0 d Rlt d eps0 Rlt d 1 Rlt d 1 Rlt d 1.
An exact proof term for the current goal is (exists_eps_lt_four_pos_Euclid eps0 1 1 1 Heps0R real_1 real_1 real_1 Heps0Pos Rlt_0_1 Rlt_0_1 Rlt_0_1).
Apply Hexd to the current goal.
Let d be given.
Assume Hd: d R Rlt 0 d Rlt d eps0 Rlt d 1 Rlt d 1 Rlt d 1.
We prove the intermediate claim HdABCDE: ((((d R Rlt 0 d) Rlt d eps0) Rlt d 1) Rlt d 1).
An exact proof term for the current goal is (andEL ((((d R Rlt 0 d) Rlt d eps0) Rlt d 1) Rlt d 1) (Rlt d 1) Hd).
We prove the intermediate claim HdABCD: (((d R Rlt 0 d) Rlt d eps0) Rlt d 1).
An exact proof term for the current goal is (andEL (((d R Rlt 0 d) Rlt d eps0) Rlt d 1) (Rlt d 1) HdABCDE).
We prove the intermediate claim HdABC: ((d R Rlt 0 d) Rlt d eps0).
An exact proof term for the current goal is (andEL ((d R Rlt 0 d) Rlt d eps0) (Rlt d 1) HdABCD).
We prove the intermediate claim HdD: Rlt d 1.
An exact proof term for the current goal is (andER ((d R Rlt 0 d) Rlt d eps0) (Rlt d 1) HdABCD).
We prove the intermediate claim HdAB: d R Rlt 0 d.
An exact proof term for the current goal is (andEL (d R Rlt 0 d) (Rlt d eps0) HdABC).
We prove the intermediate claim Hdeps0: Rlt d eps0.
An exact proof term for the current goal is (andER (d R Rlt 0 d) (Rlt d eps0) HdABC).
We prove the intermediate claim HdR: d R.
An exact proof term for the current goal is (andEL (d R) (Rlt 0 d) HdAB).
We prove the intermediate claim HdPos: Rlt 0 d.
An exact proof term for the current goal is (andER (d R) (Rlt 0 d) HdAB).
We prove the intermediate claim Hddlt1: Rlt d 1.
An exact proof term for the current goal is HdD.
We prove the intermediate claim HexN: ∃N : set, N ω ∀m n : set, m ωn ωN mN nabs_SNo (add_SNo (apply_fun seq m) (minus_SNo (apply_fun seq n))) < d.
An exact proof term for the current goal is (HabsTail d HdR HdPos Hddlt1).
Apply HexN to the current goal.
Let N be given.
Assume HNpair.
We use N to witness the existential quantifier.
Apply andI to the current goal.
An exact proof term for the current goal is (andEL (N ω) (∀m n : set, m ωn ωN mN nabs_SNo (add_SNo (apply_fun seq m) (minus_SNo (apply_fun seq n))) < d) HNpair).
Let m and n be given.
Assume HmO: m ω.
Assume HnO: n ω.
Assume HNm: N m.
Assume HNn: N n.
We will prove abs_SNo (add_SNo (apply_fun seq m) (minus_SNo (apply_fun seq n))) < eps0.
We prove the intermediate claim Habd: abs_SNo (add_SNo (apply_fun seq m) (minus_SNo (apply_fun seq n))) < d.
An exact proof term for the current goal is (andER (N ω) (∀m0 n0 : set, m0 ωn0 ωN m0N n0abs_SNo (add_SNo (apply_fun seq m0) (minus_SNo (apply_fun seq n0))) < d) HNpair m n HmO HnO HNm HNn).
We prove the intermediate claim HdS: SNo d.
An exact proof term for the current goal is (real_SNo d HdR).
We prove the intermediate claim Heps0S: SNo eps0.
An exact proof term for the current goal is (real_SNo eps0 Heps0R).
We prove the intermediate claim Hdeps0S: d < eps0.
An exact proof term for the current goal is (RltE_lt d eps0 Hdeps0).
Set t to be the term add_SNo (apply_fun seq m) (minus_SNo (apply_fun seq n)).
We prove the intermediate claim HmR: apply_fun seq m R.
An exact proof term for the current goal is (Hseq m HmO).
We prove the intermediate claim HnR: apply_fun seq n R.
An exact proof term for the current goal is (Hseq n HnO).
We prove the intermediate claim HmnR: minus_SNo (apply_fun seq n) R.
An exact proof term for the current goal is (real_minus_SNo (apply_fun seq n) HnR).
We prove the intermediate claim HtR: t R.
An exact proof term for the current goal is (real_add_SNo (apply_fun seq m) HmR (minus_SNo (apply_fun seq n)) HmnR).
We prove the intermediate claim HabsR: abs_SNo t R.
An exact proof term for the current goal is (abs_SNo_in_R t HtR).
We prove the intermediate claim HabsS: SNo (abs_SNo t).
An exact proof term for the current goal is (real_SNo (abs_SNo t) HabsR).
An exact proof term for the current goal is (SNoLt_tra (abs_SNo (add_SNo (apply_fun seq m) (minus_SNo (apply_fun seq n)))) d eps0 HabsS HdS Heps0S Habd Hdeps0S).
We prove the intermediate claim HexStd: ∃x : set, converges_to R R_standard_topology seq x.
An exact proof term for the current goal is (abs_Cauchy_sequence_converges_R_standard_topology seq Hseq HabC).
Apply HexStd to the current goal.
Let x be given.
Assume HxStd: converges_to R R_standard_topology seq x.
We use x to witness the existential quantifier.
We will prove converges_to R (metric_topology R R_bounded_metric) seq x.
rewrite the current goal using metric_topology_R_bounded_metric_eq_R_standard_topology (from left to right).
An exact proof term for the current goal is HxStd.