User blog comment:Lord Aspect/Silly attempts to create really huge number/@comment-32783837-20180317112051

3↑↑↑n < σ(n) < 3↑↑↑(n+1)

3↑↑↑↑k < (k)σ1 < 3↑↑↑↑(k+1)

Σ ≈ 3↑↑↑↑↑8