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A321863
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a(n) = A321858(prime(n)).
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14
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0, 0, 1, 2, 1, 0, 1, 2, 1, 2, 3, 2, 3, 4, 3, 4, 3, 2, 3, 2, 1, 2, 1, 2, 1, 2, 3, 2, 1, 2, 3, 2, 3, 4, 5, 6, 5, 6, 5, 6, 5, 4, 3, 2, 3, 4, 5, 6, 5, 4, 5, 4, 3, 2, 3, 2, 3, 4, 3, 4, 5, 6, 7, 6, 5, 6, 7, 6, 5, 4, 5, 4, 5, 4, 5, 4, 5, 4, 5, 4, 3, 2, 1, 0, 1, 0, 1
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OFFSET
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1,4
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COMMENTS
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Among the first 10000 terms there are only 291 negative ones, with the earliest one being a(6181) = -1. See the comments about "Chebyshev's bias" in A321858.
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LINKS
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FORMULA
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a(n) = -Sum_{primes p<=n} Kronecker(12,prime(i)) = -Sum_{i=1..n} A110161(prime(i)).
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EXAMPLE
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prime(25) = 97, Pi(12,1)(97) = 5, Pi(12,5)(97) = Pi(12,7)(97) = Pi(12,11)(97) = 6, so a(25) = 6 + 6 - 5 - 6 = 1.
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PROG
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(PARI) a(n) = -sum(i=1, n, kronecker(12, prime(i)))
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CROSSREFS
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Let d be a fundamental discriminant.
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KEYWORD
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sign
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AUTHOR
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STATUS
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approved
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