edit-tab-stops
edit-tab-stops is an interactive compiled Lisp function in `indent.el
'.
(edit-tab-stops)
Edit the tab stops used by `tab-to-tab-stop'.
Creates a buffer *Tab Stops* containing text describing the tab stops.
A colon indicates a column where there is a tab stop.
You can add or remove colons and then do C-c C-c to make changes take effect.