let so is a polynomial ofdegree 9with9 rootst = 1, 2, ... , 9. thus

for some constant now in (1) put t = 0 to to get: therefore (1) becomes:

finally in (2) put t = 10 to get: which gives us:

Remark: it's clear that the problem can be easily generalized in different ways and the above method will still work quite nicely!