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 A177866 Numbers n such that 10^n - 69 is prime. 1
 2, 4, 6, 7, 8, 14, 20, 110, 138, 140, 145, 300, 390, 1484, 3194, 3300, 3950, 4986, 5574, 5630, 5874, 8866, 11390, 45130, 86110 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS The next term, if it exists, is > 100000. See Kamada link - primecount.txt for terms, primesize.txt for discovery details including probable or proved primes - search on "99931". LINKS Makoto Kamada, List of near-repdigit-related prime numbers. EXAMPLE 10^6 - 69 = 999931 which is a prime number. MATHEMATICA m=1000; For[n=1, n

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Last modified October 18 15:41 EDT 2019. Contains 328162 sequences. (Running on oeis4.)