On January 18 I published some puzzles with the digits 1-9, each one to be used exactly once. In a publication by Denksport, the largest Dutch puzzle publisher, I found Ikura. Ikura in Japanese is the name of salmon caviar, and the first 20-50 hits in the duckduckgo search engine mostly referred to sushi and crosswords, so I guess Denksport made up this name themselves.
Below you find some examples of puzzles of this kind.
You can check your solution here
New puzzles are published at least twice a month on Fridays. Solutions are published after one or more weeks. You are welcome to remark on the difficulty level of the puzzles, discuss alternate solutions, and so on. Puzzles are rated on a scale of 1 to 5 stars.