n=7*2309+7*688=7(2309+688)=7*2997 deci divizibil cu 7
a=3794*14-14=14*(3794-1)=14*3793 deci divizibil cu 14
x=57940*37-34*57894 = 46 deci 46 divizibil cu x
b=3+5+7+9+...+729 =
nr termeni=( 729-3):2+1=364 termeni
=3+(3+2)+(3+4)+(3+6)+...+(3+726) =
= 3*364+2+4+6+....+726=
=3*364+2(1+2+...+363)=
=3*364+2*363*364/2=
=3*364+363*364=
=364*366=3*122*364 deci divizibil cu 3
