(This post is part of the Genuinely Approachable Sudoku (GAS) series.)
This outside clue puzzle style uses different sets of paired cells to indicate sum constraints. Can you figure out all the arithmetic to get back to Sudoku logic?

PDF

or solve online (using SudokuPad)

Author/Opus: This is the 44th puzzle from Bill Murphy, part of the Genuinely Approachable Sudoku (GAS) team.

Rules: Standard Sudoku rules (insert a number from 1 to 9 into each cell so that no number repeats in any row, column, or bold region). Clues to the left and right of the grid indicate the sum of the values in the second and third cells seen in that direction; these pairs of cells are also marked by white dots. Clues to the top and bottom of the grid indicate the sum of the values in the third and fourth cells seen in that direction; these pairs of cells are also marked by gray dots.

GAS Time Standards (highlight to view): Two party hats (🎩🥳): 7:00; One party hat (🥳): 13:00. All other solvers earn a 🦕: Additive Aragosaurus.

Thomas Hits the GAS (highlight to view): 2:37, with SudokuPad replay file shared as a download for now (requires loading via settings menu with improvements expected before people should use this regularly).

Solution: PDF; solving video with explanation to be added later from GAS team.

Note: Follow this link for other less common variations of Sudoku.

Note 2: Comments on the blog are great! For a more interactive discussion, please also consider using our Daily GAS discussion post on the GMPuzzles Discord. Not a member of the Discord? Click this link for basic access.