[tex] \text{Avem~progresia~aritmetic\u{a}: }1,5,9,13,17,a_6,...,a_{10},...\\ \\ \boxed{a_{n} = a_{1}+(n-1)\cdot r}\rightarrow \text{ formula termenului general.}\\ \\ \\ a_{10} = a_{1}+(10-1)\cdot 4 = 1+9\cdot 4 = 37 \\ \\ \Rightarrow \boxed{a_{10} = 37} [/tex]
