lodof.spad line 1 [edit on github]
SetOfMIntegersInOneToN implements the subsets of M integers in the interval [1..n]
delta(S, k, p) returns the number of elements of S which are strictly between p and the k^th element of S.
elements(S) returns the list of the elements of S in increasing order.
enumerate() returns a vector of all the sets of M integers in 1..n.
incrementKthElement(S, k) increments the k^th element of S, and returns "failed" if the result is not a set of M integers in 1..n any more.
member?(p, s) returns true is p is in s, false otherwise.
replaceKthElement(S, k, p) replaces the k^th element of S by p, and returns "failed" if the result is not a set of M integers in 1..n any more.
setOfMinN([a_1, ..., a_m]) returns the set a_1, ..., a_m. Error if a_1, ..., a_m is not a set of M integers in 1..n.