73 is the best prime
already know the popular Dr. Sheldon Cooper's
"The best number is 73. Why? 73 is the 21st prime
number. Its mirror (37) is the 12th and its mirror (21)
In our terms:
If n=12, p(r(n))=r(p(n))........(1)
Q. Can you get a larger solution for
(1) or prove that there are no more solutions for n>12?
Note1: non-elegant solutions come when n & p(n) are both palindromes.
Here we do not consider these solutions that -BTW- are the matter of
our old Puzzle 51 that remains stuck
Note2: I should
thank to my friend Jaime Ayala
for let me know about this popular claim.