%I A007700 M1406
%S A007700 2,5,11,41,89,179,359,509,719,1019,1031,1229,1409,1451,1481,
%T A007700 1511,1811,1889,1901,1931,2459,2699,2819,3449,3491,3539,3821,
%U A007700 3911,5081,5399,5441,5849,6101,6131,6449,7079,7151,7349,7901
%N A007700 n, 2n+1, 4n+3 all prime.
%C A007700 Primes 2n+1 and 4n+3 respectively have n-1 and 2n primitive roots. -
Lekraj Beedassy (blekraj(AT)yahoo.com), Jan 07 2005
%D A007700 N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences,
Academic Press, 1995 (includes this sequence).
%D A007700 L. Blum; M. Blum; M. Shub, A simple unpredictable pseudorandom number
generator. SIAM J. Comput. 15 (1986), no. 2, 364-383.
%D A007700 T. Moreau, personal communication.
%H A007700 T. D. Noe, <a href="b007700.txt">Table of n, a(n) for n=1..10000</a>
%p A007700 A007700 := proc(n) local p1,p2; p1 := 2*n+1; p2 := 2*p1+1; if isprime(n)
= true and isprime(p1)=true and isprime(p2)=true then RETURN(n);
fi; end;
%t A007700 Select[Range[10^3*3], PrimeQ[ # ]&&PrimeQ[2*#+1]&&PrimeQ[4*#+3] &] (from
Vladimir Orlovsky (4vladimir(AT)gmail.com), Apr 29 2008)
%Y A007700 Cf. (A005384 and A005385), A023272, A023302, A023330, A057331, A005602.
%Y A007700 Sequence in context: A056302 A065850 A106886 this_sequence A071313 A128231
A121981
%Y A007700 Adjacent sequences: A007697 A007698 A007699 this_sequence A007701 A007702
A007703
%K A007700 nonn
%O A007700 1,1
%A A007700 N. J. A. Sloane (njas(AT)research.att.com), Simon Plouffe (simon.plouffe(AT)gmail.com)
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