Is This Prime?
Can you tell which numbers are prime?
Is This Prime? launched on March 8, 2016 with 80 votes, #720 of 4,409 launches that month and more than 75% of that year's launches. The site was still online in September 2026, 10 years on.
Does a similar job
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I made an interactive math crossword puzzle with infinite levels2024 · scientific.place · ▲165Hey there! I'm the brains behind the math crossword game on my site. This game is all about making math a little more fun – users just drag and drop numbers to fill in the blanks and move on to the next level if they get it right. Let me know if face any issues or have any suggestions! :)
Primeval Numbers2024 · aravind.rs · ▲25- ZAZero – an HTML5 game about modular arithmetic and prime numbers2015 · zero.karaniwan.org · ▲39

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Source: Product Hunt launch ↗
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