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A294067
Row 4 in rectangular array A292929.
5
2, -4, 8, -12, 24, -40, 38, -96, 138, -134, 316, -384, 384, -790, 982, -1168, 1976, -2400, 2904, -4464, 5632, -6956, 9904, -12320, 15186, -20938, 26000, -32008, 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
OFFSET
0,1
LINKS
EXAMPLE
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 +...
MATHEMATICA
nmax = 55; kmax = Ceiling[Sqrt[nmax]]+1;
Q[q_] := Sum[(x - q^k)^k, {k, -kmax, kmax}];
S[q_] := Sqrt[Q[q]/Q[-q]];
row[n_] := (1/q^n)*SeriesCoefficient[Sqrt[Q[q]/Q[-q]], {x, 0, n} ] + O[q]^nmax // CoefficientList[#, q] &;
row[4] (* Jean-François Alcover, Nov 04 2017 *)
CROSSREFS
KEYWORD
sign
AUTHOR
Paul D. Hanna, Oct 23 2017
STATUS
approved