Talk:Titanic Prime consisting of 111 Blocks of each Digit plus Zeroes

Yep, I am 90% sure this is not prime: $397$ is a factor.

The expression I used is: ((10^111-1)/9*(10^888 + 2*10^777 + 3*10^666 + 4*10^555 + 5*10^444 + 6*10^333 + 7*10^222 + 8*10^111 + 9))*10^x+1

Replace x with the number of zeroes + 1.

For $1 \le x < 5000$, I have found 3 primes. (took around 2 hours)

They have $399, 1667$ and $1917$ zeros respectively.

I doubt it is a typo this time. --RandomUndergrad (talk) 15:30, 6 March 2022 (UTC)


 * Right okay, I *really* need to do some research on this to find out what the sources say. I will take some time to do that but probably not today. --prime mover (talk) 16:08, 6 March 2022 (UTC)


 * Actually it's rather a basic-comprehension-of-arithmetic error.


 * This is how the prime is described on the Harvey Dubner list on Prime Pages (get to it from https://primes.utm.edu/bios/page.php?id=5 ):


 * $123456789 · (R(999)/R(9)) · 10^{2285} + 1$


 * which is $(123456789)_{111} (0)_{2284} 1$ and not in any way $\paren 1_{111} \paren 2_{111} \paren 3_{111} \paren 4_{111} \paren 5_{111} \paren 6_{111} \paren 7_{111} \paren 8_{111} \paren 9_{111} \paren 0_{2284} 1$.


 * As for $123456789 · (R(999)/R(9)) · 10^{2285} + 1$:


 * Again, an errata page is needed. I am wondering whether to get in touch with David Wells (he lives not far from me) but I doubt he'd be impressed to learn his most influential work has $175$ mistakes in it. --prime mover (talk) 16:50, 6 March 2022 (UTC)


 * Completely forgot the Prime Pages have pages for the discoverers of big primes, listing their discoveries.


 * Then we should be fine after the title of this page is changed slightly. --RandomUndergrad (talk) 17:47, 6 March 2022 (UTC)


 * job done --prime mover (talk) 20:34, 6 March 2022 (UTC)