This is LaTeX code:

[latex]
 
\displaystyle\left(\left\lfloor\frac{k}{2}\right\rfloor-\left\lfloor\frac{k}{3}\right\rfloor\right)\left(\frac{3}{2}\left(\left\lfloor\frac{k}{2}\right\rfloor+\left\lfloor\frac{k}{3}\right\rfloor\right)-k+\frac{3}{2}\right)+\\
+\displaystyle\left(\left\lfloor\frac{k+1}{2}\right\rfloor-\left\lfloor\frac{k+1}{3}\right\rfloor\right)\left(\frac{3}{2}\left(\left\lfloor\frac{k+1}{2}\right\rfloor+\left\lfloor\frac{k+1}{3}\right\rfloor\right)-k+\frac{1}{2}\right)

[/latex]