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A156973
Primes of the form 2^k + 17.
2
19, 8209, 2097169, 8589934609, 2417851639229258349412369, 680564733841876926926749214863536422929, 62165404551223330269422781018352605012557018849668464680057997111644937126566671941649
OFFSET
1,1
FORMULA
a(n) = 2^A057200(n) + 17. - Elmo R. Oliveira, Nov 08 2023
EXAMPLE
19 = 2^1 + 17 is in the sequence;
8209 = 2^13 + 17 is in the sequence.
MATHEMATICA
Delete[Union[Table[If[PrimeQ[2^n + 17], 2^n + 17, 0], {n, 1, 300}]], 1]
PROG
(Magma) [ a: n in [1..400] | IsPrime(a) where a is 2^n+17 ]; // Vincenzo Librandi, Nov 27 2010
CROSSREFS
Cf. A000040, A057200, A057733 (2^k + 3), A123250 (2^k + 5), A104066 (2^k + 7), A156940 (2^k + 11), A104067 (2^k + 13).
Sequence in context: A340165 A124989 A265964 * A270972 A260005 A276739
KEYWORD
nonn
AUTHOR
Edwin Dyke (ed.dyke(AT)btinternet.com), Feb 19 2009
EXTENSIONS
a(7) from Vincenzo Librandi, Apr 29 2010
STATUS
approved