Zero Sink

Wednesday, November 24, 2010

Another world record near-repdigit palindrome prime

After I found the previous one on Halloween, another one turns up the day before Thanksgiving. This one is all nines, except for the center digit which is eight.

Primality testing 10^(2*67404+1)-1*10^67404-1 [N+1, Brillhart-Lehmer-Selfridge]
Running N+1 test using discriminant 7, base 1+sqrt(7)
Calling Brillhart-Lehmer-Selfridge with factored part 34.95%
10^(2*67404+1)-1*10^67404-1 is prime! (4490.0911s+0.0381s)

(It's better written out as 10^134809-10^67404-1 ).

Monday, November 22, 2010

7*(10^3891-1)/9-5*10^1945 is prime

The Primo certificate for 7*(10^3891-1)/9-5*10^1945 is here.

Thursday, November 11, 2010

7*(10^4489-1)/9-2*10^2244 is prime.

Here's the Primo certificate for 7*(10^4489-1)/9-2*10^2244.