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Row 4 in rectangular array A292929.
5

%I #7 Nov 04 2017 08:52:32

%S 2,-4,8,-12,24,-40,38,-96,138,-134,316,-384,384,-790,982,-1168,1976,

%T -2400,2904,-4464,5632,-6956,9904,-12320,15186,-20938,26000,-32008,

%U 42560,-52278,64458,-83736,102294,-125428,159288,-193908,236632,-295612,358170,-434364,535958,-646032,778504,-950552,1139784,-1367002,1654268,-1972508,2353214,-2825722,3355344,-3983820,4749672,-5614558,6634830

%N Row 4 in rectangular array A292929.

%H Paul D. Hanna, <a href="/A294067/b294067.txt">Table of n, a(n) for n = 0..380</a>

%e G.f.: A(q) = 2 - 4*q + 8*q^2 - 12*q^3 + 24*q^4 - 40*q^5 + 38*q^6 - 96*q^7 + 138*q^8 - 134*q^9 + 316*q^10 - 384*q^11 + 384*q^12 - 790*q^13 + 982*q^14 - 1168*q^15 + 1976*q^16 - 2400*q^17 + 2904*q^18 - 4464*q^19 + 5632*q^20 +...

%t nmax = 55; kmax = Ceiling[Sqrt[nmax]]+1;

%t Q[q_] := Sum[(x - q^k)^k, {k, -kmax, kmax}];

%t S[q_] := Sqrt[Q[q]/Q[-q]];

%t row[n_] := (1/q^n)*SeriesCoefficient[Sqrt[Q[q]/Q[-q]], {x, 0, n} ] + O[q]^nmax // CoefficientList[#, q] &;

%t row[4] (* _Jean-François Alcover_, Nov 04 2017 *)

%Y Cf. A292929, A293132, A294065, A294066.

%K sign

%O 0,1

%A _Paul D. Hanna_, Oct 23 2017