Firstly,looks like I owe everybody an apology: During the resizing of the picture in Dpaint I lost one pentominoe! Sorry dudes! Anyway, you had the fun of finding it. Thanx to Macno/Grace for pointing that out. And for those of you that missed the last issue you have them all again here. And I decided to repeat the whole article so if you're a new reader you can join in the fun also. BTW: So, far I haven't heard from anyone about the solution to 20x3 field! Looks like there isn't many geniouses out there... Anyway, I would like to start a regular Pentominoes column in the Corner. How about that? Let's make a competition and see who can find more different combinations... Let's see who is the most intelligent dude in the scene! Now, here's the original article: I found this puzzle, which is more than usual ones, in a book Mother Earth by Arthur Clark. As I found it very interesting, I decided to share it with our readers... Pentominoes are shapes made of five equal squares. Here's how to make them: take five squares and combine them together in as many as possible planar combinations. But allways in a way that they are touching only with each other's sides. You can make up a total of 12 different combinations. To help you out, I even drawn them in DPaint so you don't have to waste your time on that. Look at the next article! It's obvious that their surface adds up to 60 (12*5). As 60 is such a nice number, mathematically speaking, we can represent that number as a multiplication of various numbers, i.e. 10x6, 12x5, 15x4, 20x3. Our goal is to fit twelve pentominoes fields of such dimensions. The easiest one is 10x6. Cut pentominoes out of hard paper and try to fit them so they make a 10x6 rectangle. It will seem impossible at first. But, it isn't! Guess in how many different combinations are possible! You would never have guessed it. There is 2399 different combination! If you find at least one within first 15 minutes, you're a brainiac! The hardest field to solve is, obviously, 20x3 one. There are only two possible combinations to make. If you find them out, then consider yourself a genious. There are 12x2^21 false combinations... That's exactly 1 004 539 160 000 000!!! If computer was trying to solve it at a rate of 1 combination per second, it would take him 6 million million years... That's more than the age of the universe! But, as humans are greately superior to computers, we won't need to bang our hands 'till the end of the time, our logic and intuition can rule out a great number of them, so it's possible to find the right one in a matter of days. I know the right combination, but I won't tell ya! Am I rotten or what! If you solve this one, please call me up, or write to me... I'd like to know one of the smartest humans alive. And maybe we could make an interview with you! On the other hand, if you spend many sleepless nights trying to solve this puzzle, and you're at the verge of a nervous breakdown, contact me. I'll tell ya the combination. (In case you were wondering: No, I didn't manage to solve 20x3 field by myself...) OK, now take scissors, cut the pentominoes and let's get busy! I wish you all the luck!