And now...
Here's our February 2026 challenge!
Welcome to the new home of Ponder This, the monthly IBM Research puzzles hosted by IBM Research - Israel. You are cordially invited to match wits with some of the best minds in IBM Research.
Some of us can't see a problem without wanting to take a crack at solving it. Does that sound like you?
Good. Forge ahead and ponder this month's problem. We post a new one every month and allow a month for you to submit solutions (we may even publish submitted answers, especially if they're correct).
We usually won't reply individually to submitted solutions, but every few days we'll update the list of people who answered correctly. After the beginning of the next month, we'll post the answer.
So give your mind a break from its routine. You never know what other problems you may solve in the process!
Here's our February 2026 challenge!
solution for our December 2025 challenge
| Solver | Challenges solved | |
|---|---|---|
| 1 | Daniel Bitin | 188 |
| 2 | Dan Dima | 169 |
| 3 | David Greer | 144 |
| 4 | Radu-Alexandru Todor | 133 |
| 5 | Clive Tong | 129 |
| 6 | Motty Porat | 127 |
| 7 | Joseph DeVincentis | 118 |
| 8 | Nyles Heise | 115 |
| 9 | Todd Will | 112 |
| 10 | Daniel Chong Jyh Tar | 105 |
The current puzzlemaster of Ponder This is Gadi Aleksandrowicz. Previous puzzlemasters include Oded Margalit (2007-2020), James Shearer (2005-2009), and Don Coppersmith (1998-2005).
If you have any problems you think we might enjoy, please send them in. All replies should be sent to: ponder@il.ibm.com
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