[seqfan] Closed form is needed

[Vladimir Reshetnikov]

Hi

Any ideas how to evaluate these roots in closed form?
Or at least get more digits...

FindRoot[Derivative[0, 2][HarmonicNumber][x, 0], {x, 0.33}]
FindRoot[Derivative[0, 3][HarmonicNumber][x, 0], {x, 0.7}]

Thanks
Vladimir