18 Steps is an EP by rock artist Trey Anastasio.

Like the tracks on Bar 17, the tunes featured on 18 Steps were recorded over roughly a three-year period, from the spring of 2003 to the summer of 2006.

18 Steps can be found in select independent record stores, online auctions, and is still available for download via LivePhish.

David Steinberg (aka "Zzyzx") contributed the mathematical expression for the cover.

[1] He briefly explains it on Tom Marshall's podcast episode 4, and mentions it includes stirling numbers, phi, and the sum of a convergent series to form something like 17 + 2 - ... = 18 steps.