Suppose a2,a3,a4,a5,a6,a7are integers such that 57=a22!+a33!+a44!+a55!+a66!+a77! where 0 ≤ a< j for j= 2,4,5,6,7.
The sum a2+a3+a4+a5+a6+a7 is
9
57=2520a2+840a3+210a4+42a5+7a6+a77!
2520a2+840a3+210a4+42a5+7a6+a7=3600
Let a2=a3=a4=1 a5=0 a6=4 a7=2