fns3 http://www.openmath.org/cd/fns3.ocd 2006-06-01 2004-06-01 1 1 experimental This CD holds further functions concerning functions themselves. A particularly interesting function is function which constructs a function with given domain and range. function This symbol denotes a function constructor. When aplied to at least two arguments, which are sets, the first argument is the domain and the second the range of the function. When applied to at least three arguments, the first two of which are stes and the third of which is a lambda expression, the third argument gives the function specification. The domain of the function f constructed this way is the first argument The range of the function f constructed this way is the second argument The following object defines a function from the natural numbers into the integers specificied by the fact that n maps to n(n+1)/2. 1 2 specification This symbol denotes the specification of a function. It is a unary function. When aplied to its argument, which should be a function applied to three arguments, it returns the third argument of the function, that is, the function specification. The following object defines a function from the natural numbers into the integers specificied by the fact that n maps to n(n+1)/2. 1 2 1 2