From the definition of x, x^2-1=(1/4)(y^(2/m)+2+y^-(2/m)-1=(1/4)(y^(2/m)-2+y^-(2/m))=(1/4)(y^(1m)-y^-(1/m))^2.
We don't have a definition of any series for y, but if we put n=1 we have to prove specifically:
(1/4)(y^(1m)-y^-(1/m))^2y3+3(1/2)(y^(1/m)+y^-(1/m)y2+(1-m^2)y1=0, where y1, y2 and y3 are the first three terms of the unknown series.
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