perplexus.info :: Numbers : Reversible P and P^2

Reversible P and P^2 (Posted on 2023-10-31)

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.

Submitted by K Sengupta

Rating: 5.0000 (2 votes)

Solution: (Hide)

13 31 169 961 113 311 12769 96721 1021 1201 1042441 1442401 1031 1301 1062961 1692601 10111 11101 102232321 123232201 10211 11201 104264521 125462401 11113 31111 123498769 967894321 101021 120101 10205242441 14424250201 101111 111101 10223434321 12343432201 102121 121201 10428698641 14689682401 110221 122011 12148668841 14886684121 111031 130111 12327882961 16928872321 111121 121111 12347876641 14667874321 111211 112111 12367886521 12568876321
For an explanation, refer to the solution submitted by Larry in this location.

Comments: ( You must be logged in to post comments.)

Subject	Author	Date
This was a good Halloween puzzle.	Math Man	2023-11-01 17:49:23
re(2): No Subject	Larry	2023-10-31 21:36:47
re: No Subject	Charlie	2023-10-31 13:52:44
No Subject	Larry	2023-10-31 13:28:21

Please log in:

Login:
Password:
Remember me:

Sign up! \| Forgot password

Search:

Search body:

Forums (0)
Newest Problems
Random Problem
FAQ | About This Site
Site Statistics
New Comments (10)
Unsolved Problems
Top Rated Problems
This month's top
Most Commented On

Chatterbox:


perplexus dot info