combination (redirected from combinatory)

combination, in business

combination, in business: see trust.

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combination

1. 

a. the set of numbers that opens a combination lock

b. the mechanism of this type of lock

2. Brit a motorcycle with a sidecar attached

3. Maths

a. an arrangement of the numbers, terms, etc., of a set into specified groups without regard to order in the group

b. a group formed in this way. The number of combinations of n objects taken r at a time is n!/[(n -- r)!r!]. Symbol: _nC_r

4. the chemical reaction of two or more compounds, usually to form one other compound

5. Chess a tactical manoeuvre involving a sequence of moves and more than one piece

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1.	(mathematics)	combination - A set containing a certain number of objects selected from another set. The number of combinations of r objects chosen from a set of n is n C r = n! / ((n-r)! r!) where "n C r" is normally with n and r as subscripts or as n above r in parentheses. See also permutation.
2.	(reduction)	combination - In the theory of combinators, a combination denotes an expression in which function application is the only operation.