Let three consecutive terms are Tr,Tr+1,Tr+2
So, Crn+5Cr−1n+5=105 and Cr+1n+5Crn+5=1410
Using property Cr−1nCrn=rn−r+1, we have
r(n+5)−r+1=2 and r+1(n+5)−(r+1)+1=57
⇒n−3r+6=0 and 5n−12r+18=0
Solving both equations, n=6,r=4
Hence, the greatest coefficient will be of middle term, which is =C5n+5=C511=462