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

17, 197, 1997, 19997, 19999999999997, 199999999999997, 19999999999999999999999999999999999999999999999999999999999999999999999999997

Offset

1,1

Comments

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

Links

Table of n, a(n) for n=1..7.

Mathematica

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

Prog

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

Crossrefs

Cf. A102947.

Sequence in context: A018250 A021184 A069361 * A130817 A055432 A154276

Adjacent sequences: A177132 A177133 A177134 * A177136 A177137 A177138

Keyword

nonn

Author

Vincenzo Librandi, Dec 10 2010

Status

approved