*-operatia de inmultire
^-ridicarea la putere
b2=b1*q=>b2=5*2=>b2=10
b3=b1*q^(3-1)=>b3=5*2^2=>b3=20
b4=b1*q^(4-1)=>b4=5*2^3=>b4=40
b302=b1*q^(302-1)=>b302=5*q^301=>b302=5*2^301
S501=b1*(q^501 -1)/(q-1)=>S501=5*(2^501 -1)/(2-1)=>S501=5*(2^501 -1)
Formula termenului general:
bn=b1*q^n
Sn=b1*(q^n -1)/(q-1)