Theorem srecval | index | src |

pub theorem srecval {i: nat} (S: set) (n: nat):
  $ srec S n = S @ (\. i e. upto n, srec S i) $;
StepHypRefExpression
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)