Metamath Proof Explorer


Theorem pell14qrexpcl

Description: Positive Pell solutions are closed under integer powers. (Contributed by Stefan O'Rear, 18-Sep-2014)

Ref Expression
Assertion pell14qrexpcl D A Pell14QR D B A B Pell14QR D

Proof

Step Hyp Ref Expression
1 elznn0 B B B 0 B 0
2 simplll D A Pell14QR D B B 0 D
3 simpllr D A Pell14QR D B B 0 A Pell14QR D
4 simpr D A Pell14QR D B B 0 B 0
5 pell14qrexpclnn0 D A Pell14QR D B 0 A B Pell14QR D
6 2 3 4 5 syl3anc D A Pell14QR D B B 0 A B Pell14QR D
7 pell14qrre D A Pell14QR D A
8 7 recnd D A Pell14QR D A
9 8 ad2antrr D A Pell14QR D B B 0 A
10 simplr D A Pell14QR D B B 0 B
11 10 recnd D A Pell14QR D B B 0 B
12 simpr D A Pell14QR D B B 0 B 0
13 expneg2 A B B 0 A B = 1 A B
14 9 11 12 13 syl3anc D A Pell14QR D B B 0 A B = 1 A B
15 simplll D A Pell14QR D B B 0 D
16 simpllr D A Pell14QR D B B 0 A Pell14QR D
17 pell14qrexpclnn0 D A Pell14QR D B 0 A B Pell14QR D
18 15 16 12 17 syl3anc D A Pell14QR D B B 0 A B Pell14QR D
19 pell14qrreccl D A B Pell14QR D 1 A B Pell14QR D
20 15 18 19 syl2anc D A Pell14QR D B B 0 1 A B Pell14QR D
21 14 20 eqeltrd D A Pell14QR D B B 0 A B Pell14QR D
22 6 21 jaodan D A Pell14QR D B B 0 B 0 A B Pell14QR D
23 22 expl D A Pell14QR D B B 0 B 0 A B Pell14QR D
24 1 23 syl5bi D A Pell14QR D B A B Pell14QR D
25 24 3impia D A Pell14QR D B A B Pell14QR D