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Initial prime of exactly nine consecutive primes congruent to 3 modulo 4.
3

%I #6 Nov 21 2013 12:49:39

%S 39607,278051,339863,341827,402371,519587,735211,919423,1123219,

%T 1191643,1263239,1329763,1635547,1648919,1737863,1994119,2191687,

%U 2465227,2566279,3025423,3101743,3197899,3306731,3719467,4259243,4466411

%N Initial prime of exactly nine consecutive primes congruent to 3 modulo 4.

%C The table provides all 8949 [=A092661(9)] terms less than 10^9.

%C If 10 or more consecutive primes are all congruent to 3 modulo 4, none of them is a member of this sequence. [From Harvey P. Dale, Oct 23 2011]

%H Rick L. Shepherd, <a href="/A162866/b162866.txt">Table of n, a(n) for n=1..8949</a>

%t m9Q[l_]:=Module[{ms=Mod[l,4]},First[ms]!=3&&Last[ms]!=3&&Union[ Take[ ms,{2,10}]]=={3}]; Transpose[Select[Partition[Prime[Range[ 320000]], 11,1],m9Q]][[2]] (* _Harvey P. Dale_, Oct 23 2011 *)

%Y Cf. A092661, A162865, A055624, A057619, A054678.

%K nonn

%O 1,1

%A _Rick L. Shepherd_, Jul 15 2009