A set of numbers a1,a2,...,a100 is obtained by rearranging the numbers 1,2,...,100 . Form the numbers
b1=a1
b2=a1+a2
b3=a1+a2+a3
...
b100=a1+a2+...+a100
Prove that among the remainders on dividing the numbers by 100,11 of them are different .( L . D . Kurlyandchik , Leningrad) number theorycombinatoricsremainderSumpermutations