6-7-7-7-7-888-

Question Number 198200 by moath123111 last updated on 13/Oct/23

$$\mathrm{6}\sigma\left[\mathrm{7}\left[\mathrm{7}\left[\mathrm{7}\left[\mathrm{7}\:\right.\right.\right.\right. \\ $$$$\mathrm{888} \\ $$