One idea for a vertical city I had was a three winged tower.
This version has 6 main blocks of 100 floors each separated by a combined maintenance and nature area (M).
I decided on three wings to have both stability and a wide enough view for the residents.
The outer area is all residential apartments (R).
Each wing has a transport block at the centre (E) for elevators, stairs, etc. flanked by commercial and industrial areas (C/I). Heavy industry is placed on the lower and basement floors.
The centre of the building is an open area (O) from bottom to top.
There are on average 75 apartments per floor making a total of 44625 apartments. The lowest five floors are for special use (government, hotel, entrances, etc.)
One quarter of the height of the building is underground to provide a stable base and house equipment for renewable energy.
Energy is provided by windows with embedded solar cells and geothermal energy in addition to specialised energy towers (not shown).
Food is mostly provided by one or two vertical farms (not shown).