Let x be given.
Assume HxR.
We prove the intermediate
claim Ha0R:
a0 ∈ R.
We prove the intermediate
claim Hb0R:
b0 ∈ R.
We prove the intermediate
claim HxS:
SNo x.
An
exact proof term for the current goal is
(real_SNo x HxR).
We prove the intermediate
claim H1S:
SNo 1.
We prove the intermediate
claim Ha0ltx:
a0 < x.
We prove the intermediate
claim Hlt:
a0 < add_SNo x 0.
rewrite the current goal using
(add_SNo_0R x HxS) (from right to left) at position 2.
An exact proof term for the current goal is Hlt.
We prove the intermediate
claim Hxltb0:
x < b0.
We prove the intermediate
claim Hlt:
add_SNo x 0 < b0.
rewrite the current goal using
(add_SNo_0R x HxS) (from right to left) at position 1.
An exact proof term for the current goal is Hlt.
We prove the intermediate
claim Ha0x:
Rlt a0 x.
An
exact proof term for the current goal is
(RltI a0 x Ha0R HxR Ha0ltx).
We prove the intermediate
claim Hxb0:
Rlt x b0.
An
exact proof term for the current goal is
(RltI x b0 HxR Hb0R Hxltb0).
We prove the intermediate
claim Hconj:
Rlt a0 x ∧ Rlt x b0.
Apply andI to the current goal.
An exact proof term for the current goal is Ha0x.
An exact proof term for the current goal is Hxb0.
An
exact proof term for the current goal is
(SepI R (λx0 : set ⇒ Rlt a0 x0 ∧ Rlt x0 b0) x HxR Hconj).
∎