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A289808
Primes of the form 3^k - 28.
1
53, 701, 59021, 14348879, 31381059581, 282429536453, 7625597484959, 50031545098999679, 1144561273430837494885949696399, 26183890704263137277674192438430182020124319, 2120895147045314119491609587512844743630072079
OFFSET
1,1
LINKS
F. Firoozbakht and M. F. Hasler, Variations on Euclid's formula for Perfect Numbers, JIS 13 (2010) #10.3.1.
Henri and Renaud Lifchitz, PRP Records
OpenPFGW Project, Primality Tester
FORMULA
a(n) = 3^A219047(n) - 28. - Elmo R. Oliveira, Nov 12 2023
MATHEMATICA
Select[Table[3^k - 28], {k, 4, 100}], PrimeQ[#] &]
CROSSREFS
Cf. A000040, A219047 (corresponding k's).
Sequence in context: A219989 A027007 A142780 * A183802 A183794 A201153
KEYWORD
nonn
AUTHOR
Robert Price, Sep 02 2017
STATUS
approved