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Number of consecutive prime runs of 2 primes congruent to 3 mod 4 below 10^n.
5

%I #10 Mar 18 2018 17:27:41

%S 0,5,20,101,751,5949,49010,418366,3627049,32067600,287357618

%N Number of consecutive prime runs of 2 primes congruent to 3 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 2 primes occur before interruption by a prime congruent to 1 mod 4.

%e a(4)=101 because 101 pairs of primes occur below 10^4, each run interrupted by a prime congruent to 1 mod 4.

%Y Cf. A092640, A092641.

%K more,nonn

%O 1,2

%A _Enoch Haga_, Mar 02 2004

%E a(9)-a(11) from _Chai Wah Wu_, Mar 18 2018