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17 q-Hypergeometric and Related FunctionsProperties

§17.3 q-Elementary and q-Special Functions

Contents

§17.3(i) Elementary Functions

q-Exponential Functions

17.3.1\mathop{e_{{q}}\/}\nolimits\!\left(x\right)=\sum_{{n=0}}^{\infty}\frac{(1-q)^{%
n}x^{n}}{\left(q;q\right)_{{n}}}=\frac{1}{\left((1-q)x;q\right)_{{\infty}}},
17.3.2\mathop{E_{{q}}\/}\nolimits\!\left(x\right)=\sum_{{n=0}}^{\infty}\frac{(1-q)^{%
n}q^{{\binom{n}{2}}}x^{n}}{\left(q;q\right)_{{n}}}=\left(-(1-q)x;q\right)_{{%
\infty}}.

q-Cosine Functions

See also Suslov (2003).

§17.3(ii) Gamma and Beta Functions

See §5.18.

§17.3(iii) Bernoulli Polynomials; Euler and Stirling Numbers

q-Bernoulli Polynomials

17.3.7\mathop{\beta_{{n}}\/}\nolimits\!\left(x,q\right)=(1-q)^{{1-n}}\sum_{{r=0}}^{n%
}(-1)^{r}\binom{n}{r}\frac{r+1}{(1-q^{{r+1}})}q^{{rx}}.

q-Stirling Numbers

These were introduced in Carlitz (1954b, 1958). The \mathop{\beta_{{n}}\/}\nolimits\!\left(x,q\right) are, in fact, rational functions of q, and not necessarily polynomials. The \mathop{A_{{m,s}}\/}\nolimits\!\left(q\right) are always polynomials in q, and the \mathop{a_{{m,s}}\/}\nolimits\!\left(q\right) are polynomials in q for 0\leq s\leq m.

§17.3(iv) Theta Functions

See §§17.8 and 20.5.

§17.3(v) Orthogonal Polynomials

See §§18.2718.29.