relaxin99 Senior | Next Rank: 100 Posts View User Profile Posts: 73 Joined: Tue Sep 16, 2008 4:33 pm Thanked: 2 times Sequence by relaxin99 » Thu Feb 26, 2009 5:22 pm The sequence a1, a2, a3......an of n integers is such that ak = - 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 Top Quote
