U(1 la 33)=1
u(4 la 34)=6
4la 1=4
4 la a 2=..6
(Se repeta din 2 in 2). 34:2:17 r0=>u(4la 34)=6
U(7 la 35)=3
7la 1=7
7 la 2=..9
7 la 3=...3
7 la 4=..1
(Se repeta din 4 in 4). 35:4=8 r3=> u(7 la 35)=3
U(a)= u(1la 33) + u(4la 34) + u(7 la35)
U(a)= u(1+6+3)=u(10)= 0