# calculates probability of shared birthday
# in group of n people, for n in 1:100
#
# first initialize vector of probs
probcomp = rep(NA, times=100)
#
# now begin loop through values of n
for (n in 1:100) {
#
# initialize the complement probability
   probcomp[n] = 1
#
# now begin loop to calculate product
   for (i in 1:n) {
      probcomp[n]=probcomp[n]*(365-i+1)/365
   }
}
#
# now prepare to graph results
numpeople = (1:n)
probshare = 1 - probcomp
plot(numpeople,probshare)