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A123370
Primes of the form (2^n + 7)/3.
0
3, 5, 13, 173, 699053, 3301173438094347399730997933, 15589350798196297794172638215640352209663280458413
OFFSET
1,1
COMMENTS
Corresponding n's are 1,3,5,9,21,93 (all but n=3 are of the form n=4m+1, m=0,1,2,5,23...). Cf. A123250 = primes of the form 2^n + 5.
MATHEMATICA
Select[(2^Range[0, 1000]+7)/3, PrimeQ] (* Harvey P. Dale, May 20 2013 *)
CROSSREFS
Cf. A123250.
Sequence in context: A121533 A187733 A087170 * A110407 A340037 A062698
KEYWORD
nonn
AUTHOR
Zak Seidov, Oct 12 2006
EXTENSIONS
a(7) from Harvey P. Dale, May 20 2013
STATUS
approved