Problems & Puzzles: Puzzles

Puzzle 591. 1304119699 Recently I got a new record for a class of primes that was being reported by Norman Luhn to the popular Prime Curios! Replace any single digit of 1304119699 with a 7 and the result is always prime. [Rivera] Which means that all the following eleven numbers are primes. 1304119699 7304119699  1704119699  1374119699  1307119699  1304719699  1304179699  1304117699  1304119799  1304119679  1304119697 Q. Can you get a larger prime of this type (for any valid digit you decide to use in the replacements)?

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Contribution came from J.K. Andersen

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Andersen wrote:

I assume the original prime must not contain the replacement digit.
There is no larger prime of this type below 10^13.

(A few hours after, this was confirmed independently by Emmanuel Vantieghem)

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