(Note: This bonus puzzle is being posted today to mark the occasion of Prasanna’s birthday.)
Theme: 28 from 03/02 1991-2019
Author/Opus: This is the 173rd puzzle from our contributing puzzlemaster Prasanna Seshadri.
Rules: Standard Sudoku rules. The numbers outside the grid indicate the sum of all digits between the 8 and the 9 in that row or column. Also, as in Consecutive Pairs Sudoku, if a grey circle is given between two adjacent cells, then the two numbers in those cells must be consecutive. (Note: not all grey circles are given; adjacent cells without a circle may contain either consecutive numbers or nonconsecutive numbers.)
Answer String: Enter the 1st row from left to right, followed by a comma, followed by the 7th row from left to right.
Time Standards (highlight to view): Grandmaster = 6:45, Master = 10:00, Expert = 20:00