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A294066
Row 3 in rectangular array A292929.
5
2, -4, 8, -12, 20, -44, 52, -76, 136, -164, 252, -396, 482, -684, 990, -1272, 1748, -2388, 3038, -4020, 5358, -6796, 8820, -11448, 14334, -18304, 23320, -28940, 36444, -45708, 56340, -70056, 86698, -106056, 130400, -159852, 194166, -236452, 287272, -346544, 418746, -504800, 604946, -725756, 868892, -1035456, 1234410, -1468436, 1740602, -2063076, 2440838, -2879056, 3394228, -3995400, 4690976
OFFSET
0,1
LINKS
EXAMPLE
G.f.: A(q) = 2 - 4*q + 8*q^2 - 12*q^3 + 20*q^4 - 44*q^5 + 52*q^6 - 76*q^7 + 136*q^8 - 164*q^9 + 252*q^10 - 396*q^11 + 482*q^12 - 684*q^13 + 990*q^14 - 1272*q^15 + 1748*q^16 - 2388*q^17 + 3038*q^18 - 4020*q^19 + 5358*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[3] (* Jean-François Alcover, Nov 04 2017 *)
CROSSREFS
KEYWORD
sign
AUTHOR
Paul D. Hanna, Oct 23 2017
STATUS
approved