PerformanceGoal is an option for plotting and various other algorithmic functions that specifies what aspect of performance to try to optimize with Automatic settings for ...
PermutationMin[perm] returns the smallest integer moved by the permutation perm.
PrintAction is an option for notebooks that specifies the action taken when a Print[] command is evaluated by the kernel.
PrintingPageRange is an option for notebooks that specifies the range of pages of a notebook to be printed.
PrintingStartingPageNumber is an option for notebooks that specifies what number to assign to the first page of a notebook when printed.
QGamma
(Built-in Mathematica Symbol) QGamma[z, q] gives the q-gamma function \[CapitalGamma]_q (z).
ReferenceLineStyle is an option for QuantilePlot and similar functions that specifies the style used for the reference line.
SectorSpacing is an option to PieChart and related functions that specifies radial spacing of sectors.
SimilarityRules is an option for functions such as SequenceAlignment that gives a list of rules for similarity scores to assume between pairs of elements.
SquaresR[d, n] gives the number of ways r_d (n) to represent the integer n as a sum of d squares.