Hypergeometric2F1[a, b, c, z] is the hypergeometric function \[InvisiblePrefixScriptBase]_2 F_1 (a, b; c; z).
IntegerPart[x] gives the integer part of x.
JacobiCN[u, m] gives the Jacobi elliptic function cn(u | m).
JacobiDN[u, m] gives the Jacobi elliptic function dn(u | m).
JacobiSN[u, m] gives the Jacobi elliptic function sn(u | m).
Pochhammer[a, n] gives the Pochhammer symbol (a) n.
PolyGamma[z] gives the digamma function \[Psi](z). PolyGamma[n, z] gives the n\[Null]^th derivative of the digamma function \[Psi] (n) (z).
PolyLog
(Built-in Mathematica Symbol) PolyLog[n, z] gives the polylogarithm function Li_n (z).PolyLog[n, p, z] gives the Nielsen generalized polylogarithm function S n, p (z).
Sech
(Built-in Mathematica Symbol) Sech[z] gives the hyperbolic secant of z.
Sign
(Built-in Mathematica Symbol) Sign[x] gives -1, 0, or 1 depending on whether x is negative, zero, or positive.