A279027 a(n) = number of primes of the form 4k + 3 such that 2n - 4k - 3 is prime.
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, 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, 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
Offset: 1
Keywords
Examples
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.
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