InverseJacobiDC[v, m] gives the inverse Jacobi elliptic function dc -1 (v \[VerticalSeparator] m).
InverseJacobiNC[v, m] gives the inverse Jacobi elliptic function nc -1 (v \[VerticalSeparator] m).
InverseJacobiNS[v, m] gives the inverse Jacobi elliptic function ns -1 (v \[VerticalSeparator] m).
JacobiSymbol[n, m] gives the Jacobi symbol (n/m).
KelvinBei[z] gives the Kelvin function bei(z).KelvinBei[n, z] gives the Kelvin function bei_n (z).
KelvinBer[z] gives the Kelvin function ber(z).KelvinBer[n, z] gives the Kelvin function ber_n (z).
KelvinKei[z] gives the Kelvin function kei(z).KelvinKei[n, z] gives the Kelvin function kei_n (z).
KelvinKer[z] gives the Kelvin function ker(z).KelvinKer[n, z] gives the Kelvin function ker_n (z).
Log2
(Built-in Mathematica Symbol) Log2[x] gives the base-2 logarithm of x.
LogBarnesG[z] gives the logarithm of the Barnes G-function logG(z).