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Number of consecutive prime runs of 9 primes congruent to 1 mod 4 below 10^n.
3

%I #14 Mar 18 2018 15:55:46

%S 0,0,0,0,1,6,71,851,8919,90049,894724

%N Number of consecutive prime runs of 9 primes congruent to 1 mod 4 below 10^n.

%F Generate the prime sequence with primes labeled 1 mod 4 or 3 mod 4. Add count of primes to sequence if just 9 primes occur before interruption by a prime congruent to 3 mod 4.

%e a(6)=6 because 6 sets of 9 primes occur below 10^6, each run interrupted by a prime congruent to 3 mod 4.

%Y Cf. A092661 A092662.

%Y Cf. A162865. [From _Rick L. Shepherd_, Jul 15 2009]

%K more,nonn

%O 1,6

%A _Enoch Haga_, Mar 02 2004

%E a(9) from _Rick L. Shepherd_, Jul 15 2009

%E a(10) from _Sean A. Irvine_, Oct 25 2011

%E a(11) from _Chai Wah Wu_, Mar 18 2018