The sequence $$a_1, a_2, a_3, . . . ,a_n$$ of n integers is such that $$a_k = k$$ if k is odd and $$a_k = -a_{k-1}$$ if k is even. Is the sum of the terms in the sequence positive?
(1) n is odd.
(2) $$a_n$$ is positive.
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