Let Lx, Rx, Ly and Ry be given.
Assume HLRx HLRy.
Let x and y be given.
Assume Hx Hy.
Set P1 to be the term
λu ⇒ ∃v ∈ Lx, ∃w ∈ Ry, v * y + x * w ≤ u + v * w of type
set → prop.
Set P2 to be the term
λu ⇒ ∃v ∈ Rx, ∃w ∈ Ly, v * y + x * w ≤ u + v * w of type
set → prop.
Set P to be the term λu ⇒ P1 u ∨ P2 u of type set → prop.
Apply HLRx to the current goal.
Assume H.
Apply H to the current goal.
Assume HLx HRx HLRx'.
Apply HLRy to the current goal.
Assume H.
Apply H to the current goal.
Assume HLy HRy HLRy'.
Apply SNoCutP_SNoCut_impred Lx Rx HLRx to the current goal.
rewrite the current goal using Hx (from right to left).
Assume Hx1: SNo x.
Apply SNoCutP_SNoCut_impred Ly Ry HLRy to the current goal.
rewrite the current goal using Hy (from right to left).
Assume Hy1: SNo y.
We prove the intermediate
claim Lxy:
SNo (x * y).
An
exact proof term for the current goal is
SNo_mul_SNo x y Hx1 Hy1.
We prove the intermediate
claim LI:
∀u, SNo u → SNoLev u ∈ SNoLev (x * y) → x * y < u → P u.
Apply SNoLev_ind to the current goal.
Let u be given.
Assume Hu1: SNo u.
Apply dneg to the current goal.
Assume HNC: ¬ P u.
We prove the intermediate
claim L1:
∀v ∈ Lx, ∀w ∈ Ry, u + v * w < v * y + x * w.
Let v be given.
Assume Hv.
Let w be given.
Assume Hw.
We prove the intermediate claim Lv1: SNo v.
An exact proof term for the current goal is HLx v Hv.
We prove the intermediate claim Lw1: SNo w.
An exact proof term for the current goal is HRy w Hw.
Assume H.
An exact proof term for the current goal is H.
Assume H.
Apply HNC to the current goal.
Apply orIL to the current goal.
We use v to witness the existential quantifier.
Apply andI to the current goal.
An exact proof term for the current goal is Hv.
We use w to witness the existential quantifier.
Apply andI to the current goal.
An exact proof term for the current goal is Hw.
An exact proof term for the current goal is H.
We prove the intermediate
claim L2:
∀v ∈ Rx, ∀w ∈ Ly, u + v * w < v * y + x * w.
Let v be given.
Assume Hv.
Let w be given.
Assume Hw.
We prove the intermediate claim Lv1: SNo v.
An exact proof term for the current goal is HRx v Hv.
We prove the intermediate claim Lw1: SNo w.
An exact proof term for the current goal is HLy w Hw.
Assume H.
An exact proof term for the current goal is H.
Assume H.
Apply HNC to the current goal.
Apply orIR to the current goal.
We use v to witness the existential quantifier.
Apply andI to the current goal.
An exact proof term for the current goal is Hv.
We use w to witness the existential quantifier.
Apply andI to the current goal.
An exact proof term for the current goal is Hw.
An exact proof term for the current goal is H.
Apply SNoLt_irref (x * y) to the current goal.
Apply SNoLtLe_tra (x * y) u (x * y) Lxy Hu1 Lxy Hu3 to the current goal.
Apply mul_SNoCut_abs Lx Rx Ly Ry x y HLRx HLRy Hx Hy to the current goal.
Let LxLy', RxRy', LxRy' and RxLy' be given.
Assume LxLy'E LxLy'I RxRy'E RxRy'I LxRy'E LxRy'I RxLy'E RxLy'I.
Assume HSC: SNoCutP (LxLy' ∪ RxRy') (LxRy' ∪ RxLy').
rewrite the current goal using HE (from left to right).
We will prove u ≤ SNoCut (LxLy' ∪ RxRy') (LxRy' ∪ RxLy').
rewrite the current goal using SNo_eta u Hu1 (from left to right).
We will prove SNoCut (SNoL u) (SNoR u) ≤ SNoCut (LxLy' ∪ RxRy') (LxRy' ∪ RxLy').
Apply SNoCut_Le (SNoL u) (SNoR u) (LxLy' ∪ RxRy') (LxRy' ∪ RxLy') (SNoCutP_SNoL_SNoR u Hu1) HSC to the current goal.
We will
prove ∀z ∈ SNoL u, z < SNoCut (LxLy' ∪ RxRy') (LxRy' ∪ RxLy').
Let z be given.
rewrite the current goal using HE (from right to left).
Apply SNoL_E u Hu1 z Hz to the current goal.
Assume Hz1: SNo z.
Assume Hz3: z < u.
Apply SNoLt_trichotomy_or_impred (x * y) z Lxy Hz1 to the current goal.
We prove the intermediate claim LPz: P z.
Apply IH z to the current goal.
We will
prove z ∈ SNoS_ (SNoLev u).
Apply SNoS_I2 to the current goal.
An exact proof term for the current goal is Hz1.
An exact proof term for the current goal is Hu1.
An exact proof term for the current goal is Hz2.
We will
prove SNoLev z ∈ SNoLev (x * y).
An
exact proof term for the current goal is
ordinal_TransSet (SNoLev (x * y)) (SNoLev_ordinal (x * y) Lxy) (SNoLev u) Hu2 (SNoLev z) Hz2.
An exact proof term for the current goal is H1.
Apply LPz to the current goal.
Assume H2: P1 z.
Apply H2 to the current goal.
Let v be given.
Assume H2.
Apply H2 to the current goal.
Assume H2.
Apply H2 to the current goal.
Let w be given.
Assume H2.
Apply H2 to the current goal.
We prove the intermediate claim Lv1: SNo v.
An exact proof term for the current goal is HLx v Hv.
We prove the intermediate claim Lw1: SNo w.
An exact proof term for the current goal is HRy w Hw.
We prove the intermediate
claim Lvw:
SNo (v * w).
An
exact proof term for the current goal is
SNo_mul_SNo v w Lv1 Lw1.
We prove the intermediate
claim L3:
u + v * w < z + v * w.
Apply SNoLtLe_tra (u + v * w) (v * y + x * w) (z + v * w) (SNo_add_SNo u (v * w) Hu1 Lvw) (SNo_add_SNo (v * y) (x * w) (SNo_mul_SNo v y Lv1 Hy1) (SNo_mul_SNo x w Hx1 Lw1)) (SNo_add_SNo z (v * w) Hz1 Lvw) to the current goal.
We will
prove u + v * w < v * y + x * w.
An exact proof term for the current goal is L1 v Hv w Hw.
An exact proof term for the current goal is Hvw.
We prove the intermediate claim L4: u < z.
An
exact proof term for the current goal is
add_SNo_Lt1_cancel u (v * w) z Hu1 Lvw Hz1 L3.
We will prove False.
Apply SNoLt_irref u to the current goal.
An exact proof term for the current goal is SNoLt_tra u z u Hu1 Hz1 Hu1 L4 Hz3.
Assume H2: P2 z.
Apply H2 to the current goal.
Let v be given.
Assume H2.
Apply H2 to the current goal.
Assume H2.
Apply H2 to the current goal.
Let w be given.
Assume H2.
Apply H2 to the current goal.
We prove the intermediate claim Lv1: SNo v.
An exact proof term for the current goal is HRx v Hv.
We prove the intermediate claim Lw1: SNo w.
An exact proof term for the current goal is HLy w Hw.
We prove the intermediate
claim Lvw:
SNo (v * w).
An
exact proof term for the current goal is
SNo_mul_SNo v w Lv1 Lw1.
We prove the intermediate
claim L5:
u + v * w < z + v * w.
Apply SNoLtLe_tra (u + v * w) (v * y + x * w) (z + v * w) (SNo_add_SNo u (v * w) Hu1 Lvw) (SNo_add_SNo (v * y) (x * w) (SNo_mul_SNo v y Lv1 Hy1) (SNo_mul_SNo x w Hx1 Lw1)) (SNo_add_SNo z (v * w) Hz1 Lvw) to the current goal.
We will
prove u + v * w < v * y + x * w.
An exact proof term for the current goal is L2 v Hv w Hw.
An exact proof term for the current goal is Hvw.
We prove the intermediate claim L6: u < z.
An
exact proof term for the current goal is
add_SNo_Lt1_cancel u (v * w) z Hu1 Lvw Hz1 L5.
We will prove False.
Apply SNoLt_irref u to the current goal.
An exact proof term for the current goal is SNoLt_tra u z u Hu1 Hz1 Hu1 L6 Hz3.
Apply In_no2cycle (SNoLev u) (SNoLev (x * y)) Hu2 to the current goal.
We will
prove SNoLev (x * y) ∈ SNoLev u.
rewrite the current goal using H1 (from left to right).
An exact proof term for the current goal is Hz2.
An exact proof term for the current goal is H1.
We will
prove ∀z ∈ LxRy' ∪ RxLy', SNoCut (SNoL u) (SNoR u) < z.
Let z be given.
rewrite the current goal using SNo_eta u Hu1 (from right to left).
Apply binunionE' to the current goal.
Apply LxRy'E z Hz to the current goal.
Let w0 be given.
Assume Hw0.
Let w1 be given.
Assume Hw1.
Assume Hw0a Hw1a Hw0x Hw1y Hze.
rewrite the current goal using Hze (from left to right).
We will
prove u < w0 * y + x * w1 + - w0 * w1.
We will
prove u + w0 * w1 < w0 * y + x * w1.
Apply SNoLtLe_or (u + w0 * w1) (w0 * y + x * w1) (SNo_add_SNo u (w0 * w1) Hu1 (SNo_mul_SNo w0 w1 Hw0a Hw1a)) (SNo_add_SNo (w0 * y) (x * w1) (SNo_mul_SNo w0 y Hw0a Hy1) (SNo_mul_SNo x w1 Hx1 Hw1a)) to the current goal.
Assume H.
An exact proof term for the current goal is H.
Apply HNC to the current goal.
We will prove P1 u ∨ P2 u.
Apply orIL to the current goal.
We will
prove ∃v ∈ Lx, ∃w ∈ Ry, v * y + x * w ≤ u + v * w.
We use w0 to witness the existential quantifier.
Apply andI to the current goal.
An exact proof term for the current goal is Hw0.
We use w1 to witness the existential quantifier.
Apply andI to the current goal.
An exact proof term for the current goal is Hw1.
An exact proof term for the current goal is H.
Apply RxLy'E z Hz to the current goal.
Let z0 be given.
Assume Hz0.
Let z1 be given.
Assume Hz1.
Assume Hz0a Hz1a Hz0x Hz1y Hze.
rewrite the current goal using Hze (from left to right).
We will
prove u < z0 * y + x * z1 + - z0 * z1.
We will
prove u + z0 * z1 < z0 * y + x * z1.
Apply SNoLtLe_or (u + z0 * z1) (z0 * y + x * z1) (SNo_add_SNo u (z0 * z1) Hu1 (SNo_mul_SNo z0 z1 Hz0a Hz1a)) (SNo_add_SNo (z0 * y) (x * z1) (SNo_mul_SNo z0 y Hz0a Hy1) (SNo_mul_SNo x z1 Hx1 Hz1a)) to the current goal.
Assume H.
An exact proof term for the current goal is H.
Apply HNC to the current goal.
We will prove P1 u ∨ P2 u.
Apply orIR to the current goal.
We will
prove ∃v ∈ Rx, ∃w ∈ Ly, v * y + x * w ≤ u + v * w.
We use z0 to witness the existential quantifier.
Apply andI to the current goal.
An exact proof term for the current goal is Hz0.
We use z1 to witness the existential quantifier.
Apply andI to the current goal.
An exact proof term for the current goal is Hz1.
An exact proof term for the current goal is H.
Let u be given.
Apply SNoR_E (x * y) Lxy u Hu to the current goal.
Assume Hu1: SNo u.
An exact proof term for the current goal is LI u Hu1 Hu2 Hu3.
∎