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%I #3 Mar 31 2012 10:29:52
%S 1,2,-4,8,-10,8,-8,16,-20,10,-8,24,-24,8,-16,32,-26,16,-12,24,-40,16,
%T -8,48,-40,10,-24,32,-32,24,-16,48,-52,16,-16,48,-50,8,-24,64,-40,32,
%U -16,24,-72,24,-16,80,-56,18,-28
%N Number of overpartitions of n with even rank minus the number of overpartitions of n with odd rank.
%H K. Bringmann and J. Lovejoy, <a href="http://arxiv.org/abs/0712.0631">Overpartitions and class numbers of binary quadratic forms</a>
%F G.f: 1 + 2Sum_{n >= 1} q^(n(n+1)/2)/((1+q)(1+q^2)...(1+q^n)^2).
%K sign
%O 0,2
%A _Jeremy Lovejoy_, Dec 20 2008