A108506
Integers n such that 10^n-59 is prime.
Original entry on oeis.org
2, 3, 4, 8, 20, 38, 95, 248, 263, 303, 304, 410, 438, 548, 688, 1074, 1575, 8364, 9910, 15910, 37344
Offset: 1
Julien Peter Benney (jpbenney(AT)ftml.net), Jul 06 2005
8 is a member because: n = 8 gives 10^8-59 = 100000000-59 = 99999941, which is prime.
A176987
Primes of the form 10^n-27.
Original entry on oeis.org
73, 9973, 9999973, 99999999999973, 99999999999999999973, 9999999999999999999973, 99999999999999999999999999973, 9999999999999999999999999999973, 9999999999999999999999999999999999999973
Offset: 1
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[a: n in [2..250]|IsPrime(a) where a is 10^n-27];
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Select[Table[10^n - 27, {n, 2, 500}], PrimeQ] (* Vincenzo Librandi, Jan 03 2014 *)
Select[Table[FromDigits[PadLeft[{7,3},n,9]],{n,2,40}],PrimeQ] (* Harvey P. Dale, Jul 08 2024 *)
A108493
Integers n such that 10^n-57 is prime.
Original entry on oeis.org
2, 7, 10, 11, 17, 19, 39, 49, 50, 61, 95, 106, 187, 196, 849, 889, 6436, 7370, 14446, 19647, 34399, 39922, 81297, 84305
Offset: 1
Julien Peter Benney (jpbenney(AT)ftml.net), Jul 06 2005
n = 7 is a member because: 10^7-57 = 10000000-57 = 9999943, which is prime.
Showing 1-3 of 3 results.
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