A foundational idea in Mathematica is that all expressions—whatever they may represent—ultimately have a uniform tree-like structure.

Power series are in many ways the algebraic analog of limited-precision numbers. Mathematica can generate series approximations to virtually any combination of built-in ...

You can manipulate lists of transformation rules in Mathematica just like other symbolic expressions. It is common to assign a name to a rule or set of rules. This assigns ...

FlattenAt[list, n] flattens out a sublist that appears as the n\[Null] th element of list. If n is negative, the position is counted from the end. FlattenAt[expr, {i, j, ...

PermutationCycles[perm] gives a disjoint cycle representation of permutation perm.

Find Cell Tag opens a submenu to find and select cells based on their cell tags.

Tally[list] tallies the elements in list, listing all distinct elements together with their multiplicities.Tally[list, test] uses test to determine whether pairs of elements ...

PermutationList[perm] returns a permutation list representation of permutation perm.PermutationList[perm, len] returns a permutation list of length len.