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Number of primes of the form 4k+3 such that 4(n - k) - 3 is 1 or prime where (4k+3)/3 >= n.
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%I #26 Dec 26 2016 10:22:56

%S 1,1,1,0,1,2,1,1,1,0,1,2,1,1,2,1,1,3,2,2,4,2,1,2,1,1,2,1,1,2,1,1,3,2,

%T 2,3,1,2,3,1,3,5,2,2,5,2,1,4,3,2,4,3,2,4,3,2,5,3,2,5,3,1,6,3,2,4,4,2,

%U 4,4,3,4,3,2,5,2,2,6,2,2,6,1,2,4,1,2,4,2,1,5,3,3,5,2,3,6,3

%N Number of primes of the form 4k+3 such that 4(n - k) - 3 is 1 or prime where (4k+3)/3 >= n.

%C Where 4(n - k) - 3 is a positive noncomposite number of the form 4m+1 (A280084).

%e a(6) = 2 because 4*6 = 1 + 23 where (4*5+3)/3 = 23/3 > 6 and 4*6 = 5 + 19 where (4*4+3)/3 = 19/3 > 6.

%Y Cf. A002144, A006005, A280084.

%K nonn

%O 1,6

%A _Juri-Stepan Gerasimov_, Dec 24 2016