Frame Sudoku #41

In each cell of the 9x9 grid, enter a number in the range 1–9. Each number must appear exactly once in each row, column, and block.
Additional rules: A number at the edge of the grid indicates the sum of the first three numbers that you "see" when you "look into" the grid at that point.

Calculator gives all the valid combinations for a given sum and number of digits. You can also use the combination tables
Short manual