continued fraction for a ratio of modified Bessel functions I am looking for a continued fraction for ratio* $K_2/K_1$, $K_n$ being the $2$nd-kind modified Bessel fct of order $n$.


*

*my original equivalent problem regarding ratio $${dK1(x)\over dx}/K1(x)$$ for a real $x$


I think there is a way to express this ratio in terms of a continued fraction. The idea can be found in a paper by N.M. Temme. You can also find this information on page 239 of this link:
http://apps.nrbook.com/fortran/index.html
(see Eqs. 6.7.24 to 6.7.27)
