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%I #15 Oct 14 2017 02:14:22
%S 0,1,0,-3,-2,1,4,4,2,0,-4,-5,-6,-4,4,7,2,-4,-2,2,4,8,8,5,4,0,-12,-15,
%T -14,-18,-16,-7,8,15,18,20,14,13,16,12,8,0,-12,-22,-26,-26,-26,-16,-4,
%U -3,2,12,22,24,8,-1,0,0,0,5,8,18,16,6,2,-2,4,-1,-12,-15,-10,-9,-12,-8,-10,-12,-8,-10
%N G.f.: ((1+q)/(1-q))*q*Product_{k>=1} (1 - q^k)^2*(1 - q^(11*k))^2.
%C This was presumably intended to be A006571, but the published g.f. contains a misprint - namely, the first (1-q^2) on page 1058 of the review should be (1-q)^2.
%H A. W. Knapp, <a href="http://www.ams.org/notices/201409/rnoti-p1056.pdf">Review of "Love and Math: The Heart of Hidden Reality" by E. Frenkel</a>, Notices Amer. Math. Soc., 61 (2014), pp. 1056-1060; see p. 1058.
%o (PARI) m = 50; concat(0, Vec(((1+q)/(1-q))*q*prod(k=1, m, (1 - q^k)^2*(1 - q^(11*k))^2) + O(q^m))) \\ _Michel Marcus_, Oct 13 2017
%Y Cf. A006571.
%K sign
%O 0,4
%A _N. J. A. Sloane_, Sep 22 2014