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A177141
Primes of the form (6*10^k-7)
1
53, 593, 599993, 5999993, 59999993, 599999999993, 599999999999999993, 599999999999999999999999999993, 5999999999999999999999999999999999999999993, 599999999999999999999999999999999999999999999993
OFFSET
1,1
COMMENTS
The next term -- a(11) -- has 97 digits. - Harvey P. Dale, Nov 15 2021
LINKS
FORMULA
a(n) = 6 * 10^A103025(n) - 7. - Robert Israel, Jan 22 2024
MAPLE
select(isprime, [seq(6*10^k-7, k=1..100)]); # Robert Israel, Jan 22 2024
MATHEMATICA
able[10 FromDigits[PadRight[{5}, n, 9]]+3, {n, 50}], PrimeQ] (* Harvey P. Dale, Nov 15 2021 *)
PROG
(Magma) [a: n in [0..250]|IsPrime(a) where a is 6*10^n-7]
CROSSREFS
Cf. A103025.
Sequence in context: A201855 A112749 A245589 * A096707 A219989 A027007
KEYWORD
nonn
AUTHOR
Vincenzo Librandi, Dec 10 2010
STATUS
approved