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Problems & Puzzles:
Puzzles
Puzzle 1264 A
follow up to
Puzzle 973
In 2009, J. K.
Andersen got the following twin & empirps:
10^499+X+/-1 for X=174295123052
10^499+174295123052
+1 is prime
10^499+174295123052
-1 is prime
Rev(10^499+174295123052
+1) is prime
Rev(10^499+174295123052
-1) is prime
(The four 500 digits primes verified by CR
using
ECM)
Perhaps it's time to get something larger than this.
Q. Find larger examples of these
kind
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From April 4-11, 2026, contributions came from Simon Cavegn
***
Simon wrote:
182348281 * 10^1000 + 775222951
182348281 * 10^1000 + 775222951 + 2
RevDigits(182348281 * 10^1000 + 775222951, 10)
RevDigits(182348281 * 10^1000 + 775222951 + 2, 10)
1009
digits primes.
***
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