#pseudo...
draw 99 random numbers for the first value
knock out dups      # which is do-able at part of step one by 
                    # stuffing the drawn numbers as keys to a hash
rinse, repeat as necessary

draw 99 more; 
combine as values for your hash
test that they satisfy your spec # except for the "make it impossible for 
                                 # the rand function ...."
                                 # which ain't possible by any direct method!
remove unacceptable pairs        # perhaps the test for (1,23) & (23,1) 
                                 #should occur in prior step
rinse, repeat
succeed.