pub theorem srecval {i: nat} (S: set) (n: nat):
$ srec S n = S @ (\. i e. upto n, srec S i) $;
Step | Hyp | Ref | Expression |
1 |
|
eqtr4 |
srec S n = S @ srecaux S n -> S @ (\. i e. upto n, srec S i) = S @ srecaux S n -> srec S n = S @ (\. i e. upto n, srec S i) |
2 |
|
srecval2 |
srec S n = S @ srecaux S n |
3 |
1, 2 |
ax_mp |
S @ (\. i e. upto n, srec S i) = S @ srecaux S n -> srec S n = S @ (\. i e. upto n, srec S i) |
4 |
|
appeq2 |
\. i e. upto n, srec S i = srecaux S n -> S @ (\. i e. upto n, srec S i) = S @ srecaux S n |
5 |
|
eqtr |
\. i e. upto n, srec S i = lower (srecaux S n) -> lower (srecaux S n) = srecaux S n -> \. i e. upto n, srec S i = srecaux S n |
6 |
|
lowereq |
(\ i, srec S i) |` upto n == srecaux S n -> lower ((\ i, srec S i) |` upto n) = lower (srecaux S n) |
7 |
6 |
conv rlam |
(\ i, srec S i) |` upto n == srecaux S n -> \. i e. upto n, srec S i = lower (srecaux S n) |
8 |
|
srecres |
(\ i, srec S i) |` upto n == srecaux S n |
9 |
7, 8 |
ax_mp |
\. i e. upto n, srec S i = lower (srecaux S n) |
10 |
5, 9 |
ax_mp |
lower (srecaux S n) = srecaux S n -> \. i e. upto n, srec S i = srecaux S n |
11 |
|
lowerns |
lower (srecaux S n) = srecaux S n |
12 |
10, 11 |
ax_mp |
\. i e. upto n, srec S i = srecaux S n |
13 |
4, 12 |
ax_mp |
S @ (\. i e. upto n, srec S i) = S @ srecaux S n |
14 |
3, 13 |
ax_mp |
srec S n = S @ (\. i e. upto n, srec S i) |
Axiom use
axs_prop_calc
(ax_1,
ax_2,
ax_3,
ax_mp,
itru),
axs_pred_calc
(ax_gen,
ax_4,
ax_5,
ax_6,
ax_7,
ax_10,
ax_11,
ax_12),
axs_set
(elab,
ax_8),
axs_the
(theid,
the0),
axs_peano
(peano1,
peano2,
peano5,
addeq,
muleq,
add0,
addS,
mul0,
mulS)