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A177135 Primes of the form 2*10^n - 3. 0

%I

%S 17,197,1997,19997,19999999999997,199999999999997,

%T 19999999999999999999999999999999999999999999999999999999999999999999999999997

%N Primes of the form 2*10^n - 3.

%C a(8) has 238 digits, a(9) has 873 digits and a(10) has 989 digits.

%t Select[Table[FromDigits[Join[{1},PadLeft[{},n,9],{7}]],{n,0,1000}],PrimeQ] (* _Harvey P. Dale_, Oct 30 2011 *)

%o (MAGMA) [a: n in [0..250] | IsPrime(a) where a is 2*10^n-3];

%Y Cf. A102947.

%K nonn

%O 1,1

%A _Vincenzo Librandi_, Dec 10 2010

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Last modified January 21 16:47 EST 2020. Contains 331114 sequences. (Running on oeis4.)