\[w_{1}(a,x)=e^{-\frac{1}{4}ix^{2}}M\left(\tfrac{1}{4}-\tfrac{1}{2}ia,\tfrac{1}{%
2},\tfrac{1}{2}ix^{2}\right)=e^{\frac{1}{4}ix^{2}}M\left(\tfrac{1}{4}+\tfrac{1%
}{2}ia,\tfrac{1}{2},-\tfrac{1}{2}ix^{2}\right),\]