mma` is the gamma function and :math:`J_v` is the
Bessel function of the first kind.

Parameters
----------
v : float
    Order of the Lambda function
x : float
    Value at which to evaluate the function and derivatives

Returns
-------
vl : ndarray
    Values of Lambda_vi(x), for vi=v-int(v), vi=1+v-int(v), ..., vi=v.
dl : ndarray
    Derivatives Lambda_vi'(x), for vi=v-int(v), vi=1+v-int(v), ..., vi=v.

References
----------
.. [1] Zhang, Shanjie and Jin, Jianming. "Computation of Special
       Functions", John Wiley and Sons, 1996.
       https://people.sc.fsu.edu/~jburkardt/f77_src/special_functions/special_functions.html
.. [2] Jahnke, E. and Emde, F. "Tables of Functions with Formulae and
       Curves" (4th ed.), Dover, 1945
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