[GiNaC-list] series((x+x^2)^2,x,0) is broken

[Vitaly Magerya]

> If a series A starts with x^n, then the series 1/A *ends*, not starts,
> with 1/x^n.

OK, sorry, that's not corect. Let me say it differently:

    series(sin(x)-x, x, 2) == Order(x^2)

This does not mean

    1/series(sin(x)-x, x, 2) == Order(x^-2),

because

    series(1/(sin(x)-x), x, -2) == -6/x^3 + Order(x^-2)