Explicație pas cu pas:
1 nu e număr prim, nici număr compus
[tex] \bf 19 \implies \: numar \: prim[/tex]
[tex] \blue{\bf 52 \: \: \vdots \: \: 2}[/tex]
[tex]\bf 83 \implies \: numar \: prim[/tex]
[tex]\green{\bf 143 \: \: \vdots \: \: 13\: \: \vdots \: \:11}[/tex]
[tex]\purple{\bf 198 \: \: \vdots \: \:2\: \: \vdots \: \: 3\: \: \vdots \: \:11}[/tex]
[tex]\pink{\bf 289 \: \: \vdots \: \:17}[/tex]
[tex]\red{\bf 501 \: \: \vdots \: \:3\: \: \vdots \: \: 167}[/tex]
[tex]\blue{\bf 705 \: \: \vdots \: \:3\: \: \vdots \: \: 5\: \: \vdots \: \:47}[/tex]