Decimal representation (base 10)
•12 stones
•12dec = 1 * 10 + 2       or     1*101 + 2*100
•
•123 stones
•123dec = 1 * 100 + 2 * 10 + 3    or   1 * 102 + 2 * 101 + 3*100
•
•Ndec = an*10n + an-1*10n-2 + … + a2*102 + a1*101 + a0*100              0 <= ai <= 9
•
•                          n
•Ndec = ∑ ai*10i
•                 i=0