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Reversible P and P^2 (Posted on 2023-10-31) Difficulty: 3 of 5
The prime P=13 reverses to the prime 31, and its square 169 reverses to 961, which is the square of 31.

Find additional examples where R(P)^2 = R(P^2).

Extra credit for any solution containing a digit larger than 3.

Notes:
. No palindromes like 101 or 10201.
. No modification of an existing solution by stuffing it with zeros, such as 113 modified to 1103 or 11003.

See The Solution Submitted by K Sengupta    
Rating: 5.0000 (2 votes)

Comments: ( Back to comment list | You must be logged in to post comments.)
re: No Subject | Comment 2 of 4 |
(In reply to No Subject by Larry)

The actual rule doesn't actually say the reversal of the prime must also be prime; that's just the case shown as a preliminary example.


That might have been the intension, but was not stated--only that the square of the reversal of the prime is the reversal of the square of the prime.

  Posted by Charlie on 2023-10-31 13:52:44
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