Function: hyperu
Section: transcendental
C-Name: hyperu
Prototype: GGGp
Help: hyperu(a,b,z): U-confluent hypergeometric function.
Doc: $U$-confluent hypergeometric function with complex
 parameters $a, b, z$. Note that $_{2}F_{0}(a,b,z)
 = (-z)^{-a}U(a, a+1-b, -1/z)$,
 \bprog
 ? hyperu(1, 3/2, I)
 %1 = 0.23219... - 0.80952...*I
 ? -I * hypergeom([1, 1+1-3/2], [], -1/I)
 %2 = 0.23219... - 0.80952...*I
 @eprog
