# first define n (number of objects) and N (number of repetitions)
#
match = function(n) {
#
# define x as ordered integers 1:n
x = (1:n)
#
# randomize values of x into y
y = sample(x,n,replace=FALSE)
#
# check for matches, record in match
match = (x==y)
#
# count number of matches
nummatches = sum(match)
}
#
replicate(N, match(n)) -> matchresults
hist(matchresults)
probs = table(matchresults)/N; probs
probatleastone = 1 - probs[1]; probatleastone