If $$\alpha$$ and $$\beta$$ are the roots of the equation x² + x + 1 = 0, then the equation whose roots ar $$\alpha$$¹⁹ and $$\beta$$⁷ is

If the sum of the squares of the roots of the equation $x^2-(a-2) x-(a+1)=0$ is least for an appropriate value of the variable parameter $a$, then that value of ' $a$ ' will be