Sequence help

i have a set of numbers which you can see after the graph mapper and i want to make a sequence that is going to be removing the number above it from the current number in a list, i have never made my own sequence using the command so im kinda lost. whats the move


HELP SEQUENCE.gh (7.7 KB)

just to make it more clear im aiming towards: 0.14..-0.9..=0.05… then 0.18…-0.05…=0.13… and so on

second reply here: after giving it some thought this isnt really a sequence its more so a mass subtraction? idk which command might actually be helpful here

i found the solution for anyone wondering i just shifted the list by one number grafted and then subtracted the two grafted trees