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A093612
Primes of form 7^n-2.
1
5, 47, 2399, 823541, 5764799, 13841287199, 4747561509941, 459986536544739960976799, 157775382034845806615042741, 97327453648743672783790144527749033795901408624680013074608083129650399
OFFSET
1,1
COMMENTS
The exponents n are listed in A090669, cf. formula. [From M. F. Hasler, Nov 26 2009]
The next term (a(11)) has 83 digits. - Harvey P. Dale, Nov 14 2014
FORMULA
a(n)=7^A090669(n)-2. [From M. F. Hasler, Nov 26 2009]
MATHEMATICA
Select[7^Range[90]-2, PrimeQ] (* Harvey P. Dale, Nov 14 2014 *)
CROSSREFS
Cf. A014232.
Sequence in context: A145564 A159480 A196460 * A069985 A300336 A086776
KEYWORD
nonn
AUTHOR
Arnaud Vernier, May 23 2004
EXTENSIONS
Terms beyond a(6) from M. F. Hasler, Nov 26 2009
STATUS
approved