The book is now available! 444444444
(another Prime Pages' Curiosity)
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The nth Prime Page will now find any of the first 2.623˙1015 primes or π(x) for x up to 1017.

+ 444444444 is the only nine-digit repdigit such that the product of itself and all truncations of itself minus one is prime. I.e., 444444444*44444444*4444444*444444*44444*4444*444*44*4 - 1 is prime. There are no such ten-digit repdigits. [Opao]

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