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In mathematics, an iterated binary operation
is an extension of a binary operation on a set S to a function
on finite sequences of elements of S through repeated application.[1]

Common examples include the extension of the addition operation
to the summation operation, and
the extension of the multiplication operation to the product operation.

Other operations, e.g., the set theoretic operations union and intersection,
are also often iterated, but the iterations are not given separate names.

In print, summation and product are represented by special symbols;
but other iterated operators often are denoted by larger variants of
the symbol for the ordinary binary operator.

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