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%I #33 Jan 06 2017 07:54:14
%S 0,0,1,1,2,1,3,2,2,2,3,3,4,2,4,2,4,4,3,3,4,3,3,5,6,3,6,3,2,6,5,5,6,2,
%T 6,6,6,5,8,4,6,8,7,4,12,4,5,7,4,6,8,5,6,8,8,7,10,6,5,12,4,5,10,3,8,9,
%U 7,5,10,7,7,11,8,5,14,4,8,11,7,8,10,5,5,13,12,6,14,7,6,14,10,8,14
%N a(n) = number of primes of the form 4k + 3 such that 2n - 4k - 3 is prime.
%C Conjecture: a(n) > 0 for n >= 3.
%e a(5) = 2 because 2*5 - 4*0 - 3 = 7 is prime where 4*0 + 3 = 3 is prime of the form 4k+3 and 2*5 - 4*1 - 3 = 3 is prime where 4*1 + 3 = 7 is prime of the form 4k+3.
%Y Cf. A002145, A280134.
%K nonn
%O 1,5
%A _Juri-Stepan Gerasimov_, Dec 31 2016
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