This worksheet is indeed required since it also incorporates the necessary calculation for solo 401(k) contributions despite TurboTax's naming of the form. This worksheet in TurboTax implements the worksheet from Chapter 5 of IRS Pub 560: https://www.irs.gov/pub/irs-pdf/p560.pdf
Now that you have made the necessary entries in step-by-step mode of TurboTax to populate this worksheet, view the worksheet.
