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A066413
Eisenstein-Mersenne primes: primes of the form ((3 +/- sqrt(-3))/2)^p - 1.
2
7, 271, 2269, 176419, 129159847, 1162320517, 49269609804781974450852068861184694669, 589881151426658740854227725580736348850640632297373414091790995505756623268837
OFFSET
1,1
COMMENTS
Analogs of Mersenne primes in Eisenstein integers.
The norm of a + b*w is (a+b*w)*(a+b*w^2) = a^2 - a*b + b^2.
REFERENCES
Mike Oakes, email dated Dec 24 2001 to primenumbers(AT)yahoogroups.com
EXAMPLE
For n = 7, (1-w)^7 - 1 has norm 2269, a prime.
MATHEMATICA
maxPi = 40; norm[p_] := 1 + 3^p - 2*3^(p/2)*Cos[p*Pi/6]; A066413 = {}; Do[ If[ PrimeQ[ np = norm[ Prime[k] ] ], AppendTo[ A066413, np] ], {k, 1, maxPi}]; A066413 (* Jean-François Alcover, Oct 16 2012 *)
CROSSREFS
Cf. A066408.
Sequence in context: A069449 A100465 A140031 * A332127 A222942 A289634
KEYWORD
nonn,nice
AUTHOR
Mike Oakes, Dec 24 2001
EXTENSIONS
Name changed by Arkadiusz Wesolowski, Apr 27 2012
STATUS
approved