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A102170
Primes of the form (7^k-1)/6.
4
2801, 16148168401, 85053461164796801949539541639542805770666392330682673302530819774105141531698707146930307290253537320447270457
OFFSET
1,1
COMMENTS
The next term, for k=149, has 126 digits.
MATHEMATICA
Select[(7^Range[200]-1)/6, PrimeQ]
CROSSREFS
Cf. A023000 ((7^n-1)/6), A004063 (n such that (7^n-1)/6 is prime).
Sequence in context: A292011 A306849 A022233 * A031551 A031731 A252048
KEYWORD
nonn,bref
AUTHOR
Roger L. Bagula, Mar 15 2005
STATUS
approved