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A112634
Mersenne prime indices that are not Gaussian primes.
5
2, 5, 13, 17, 61, 89, 521, 2281, 3217, 4253, 9689, 9941, 11213, 19937, 21701, 23209, 44497, 132049, 859433, 1398269, 2976221, 3021377, 6972593, 13466917, 30402457, 32582657, 42643801, 43112609, 57885161
OFFSET
1,1
COMMENTS
57885161, 74207281 and 77232917 are in this sequence as well. - Ivan Panchenko, Apr 13 2018
82589933 is in the sequence as well. - David Benjamin, Mar 30 2022
FORMULA
A000043 INTERSECT A002313. - R. J. Mathar, Oct 06 2008
A000043 SET-MINUS A112633.
MATHEMATICA
Select[MersennePrimeExponent[Range[48]], Mod[#, 4] != 3 &] (* Amiram Eldar, Oct 18 2024 *)
PROG
(PARI) is(n)=n%4 < 3 && isprime(n) && isprime(2^n-1) \\ Charles R Greathouse IV, Nov 28 2016
CROSSREFS
KEYWORD
nonn
AUTHOR
Jorge Coveiro, Dec 27 2005
EXTENSIONS
Edited by R. J. Mathar, Oct 06 2008
a(26)-a(28) from Ivan Panchenko, Apr 13 2018
a(29) from Amiram Eldar, Oct 18 2024
STATUS
approved