How to find integer points on curve

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Given the equation

$$ t^3=3a^2-3a+13 $$

I want to find integer solutions. WolframAlpha says $t=7,a=-10$ and $t=7,a=11$ are solutions, but how did it compute that?

I thought I wanted to find the intersection of $3a^2-3a+13$ and $t^3$, which gives $\approx 3.289$, but I'm not sure how to turn that into an integer.

I thought maybe solve for $a$, but I'm not sure how that helps me either

$$ a=\frac{3 \pm \sqrt{9-12(13-t^3)}}{6} $$