ButtonBar[{lbl_1 :> act_1, lbl_2 :> act_2, ...}] represents a bar of buttons with labels lbl_i that perform actions act_i when pressed.
MathieuCharacteristicA[r, q] gives the characteristic value a_r for even Mathieu functions with characteristic exponent r and parameter q.
MathieuCharacteristicB[r, q] gives the characteristic value b_r for odd Mathieu functions with characteristic exponent r and parameter q.
RamanujanTauZ[t] gives the Ramanujan tau Z-function Z(t).
Refresh
(Built-in Mathematica Symbol) Refresh[expr, opts] represents an object whose value in a Dynamic should be refreshed at times specified by the options opts. Refresh[expr, None] specifies that the value of ...
SpheroidalS1Prime[n, m, \[Gamma], z] gives the derivative with respect to z of the radial spheroidal function S_n^m, (1)(\[Gamma], z) of the first kind.
If you make a definition like f[x_]:=x Sin[x], Mathematica will store the expression x Sin[x] in a form that can be evaluated for any x. Then when you give a particular value ...
ChebyshevU[n, x] gives the Chebyshev polynomial of the second kind U_n (x).
Mathematica provides not only automatic parallelization capabilities, but also a full built-in symbolic language for specifying concurrent computation.
Hypergeometric0F1Regularized[a, z] is the regularized confluent hypergeometric function \[Null]_0 F_1 (a; z)/\[CapitalGamma](a).