You should run the input file into FastHenry2.
I get the following results:
Computed matrices (R+jL)
Row 0: n1 to n6
Freq = 10000
Row 0: 0.00344397+3.80518e-006j
Freq = 100000
Row 0: 0.00344397+3.80518e-006j
Freq = 1e+006
Row 0: 0.00344397+3.80518e-006j
Freq = 1e+007
Row 0: 0.00344397+3.80518e-006j
Freq = 1e+008
Row 0: 0.00344397+3.80518e-006j
Anyway please take care that your hi-frequency results are not correct, since you did not specify any internal discretization of the segments to model skin effect (nhinc, nwinc parameters).
Changing the input file to
.Units MM
.Default z=0 sigma=5.8e4 nhinc=7 nwinc=7
N1 x=0 y=0
N2 x=1 y=0
N3 x=1 y=2
N4 x=-1 y=2
N5 x=-1 y=0
N6 x=-0.01 y=0
E1 N1 N2 w=0.2 h=0.2
E2 N2 N3 w=0.2 h=0.2
E3 N3 N4 w=0.2 h=0.2
E4 N4 N5 w=0.2 h=0.2
E5 N5 N6 w=0.2 h=0.2
.external N1 N6
.freq fmin=1e4 fmax=1e8 ndec=1
.end
I get
Computed matrices (R+jL)
Row 0: n1 to n6
Freq = 10000
Row 0: 0.0103029+3.54403e-006j
Freq = 100000
Row 0: 0.0277283+3.44387e-006j
Freq = 1e+006
Row 0: 0.0346245+3.42846e-006j
Freq = 1e+007
Row 0: 0.0347949+3.42819e-006j
Freq = 1e+008
Row 0: 0.0347966+3.42819e-006j
Best Regards,
Enrico