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A177135 Primes of the form 2*10^n - 3. 0
17, 197, 1997, 19997, 19999999999997, 199999999999997, 19999999999999999999999999999999999999999999999999999999999999999999999999997 (list; graph; refs; listen; history; text; internal format)
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

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Last modified December 14 19:27 EST 2019. Contains 329987 sequences. (Running on oeis4.)