mental ability but a tough one

$\begin{array}{c}2^4-2^3-2^2+2\times 2=8\\3^4-3^3-3^2+2\times 3=51\\5^4-5^3-5^2+2\times 5=485\\7^4-7^3-7^2+2\times 7=2023\\11^4-11^3-11^2+2\times 11=13211\\13^4-13^3-13^2+2\times 13=26221\end{array}$