I'm working on a puzzle which requires that you hash 33 two character pairs, to map to one of two SHA256 solutions. I have 32 two character pairs, here they are: 31 31 61 44 31 77 77 79 61 30 64 43 56 34 66 6b 4c 30 31 6f 44 79 30 59 65 59 59 37 71 49 58 48 Possible characters are [a-z, A-Z, 0...

Picture shown below contains 3 horizontal and 3 vertical relations. Digits to be filled vary from 1 to 9. Order of operations is given following the arrows vertically and horizontally.

Insert four letters, which represent a place, to create what may be seen in that place.   N E T   N E T

We have a rope with a prime unit length, and we need to divide this rope into $9$ ropes by cutting it with prime and 1 unit lengths. After cutting the rope, you are supposed to find any kind of unit length (1,2,3,4...) until the original prime unit length by combining these ropes together. So...

Following on my previous puzzle that was well received (here).Note that this one is a lot shorter / easier, so feel free to participate! Can White Castle?

After hanging around this site for a little while I finally decided to put together a cipher for my first puzzle. I hope you guys enjoy it. 721036710273114701098011166107721028210373114691156812168987211178111 Don't let the length of the code intimidate you, it expanded exponentially as it ...

In a far other universe, my little sister was trapped in an cave. Surprisingly for humans, in this universe, all caves are electronic. This electronic cave had nothing but 5 buttons, two little screens, one red and one blue, a numeric keypad, and the most brought to light, this little message: M...

This is a numeric crossword: all the answers are positive numbers with no leading zeroes. Each clue is given as a sequence of mathematical operations on letters, each of which represents a distinct prime number (e.g. if $A=2$ and $B=3$ then a clue might be written as $1.\ A^A+B\quad(1)$, to wh...

Can you find what comes in place of $???$

These images seem a bit off, don't you think? The answer will be one word.

Can you complete following number sequence ? 389919, 1308, 93, ?, ? Hint:

You sit down to play a “new” game of chess. In this game only one Knight is on the regular 8x8 chessboard. Only regular legal moves of Knight are allowed. Game begins with computer going first to place the Knight at randomly selected place..say D6. It is your move to place it at any one of the ...

I recently changed my signature and have started rolling it out on forms. Here's the new one in a couple of versions so you can see the range of unimportant vs. important characteristics. What's my name and how did I construct my signature? Hint 1 Hint 2 Hint 3

Can you find the following circle in this image ? Discribe the angles at which a line intersects the circle.

What force and strength cannot get through I with a gentle touch can do; And many in the streets would stand, Were I not, as friend, at hand.

Two twins we are, and, let it not surprise,Alike in every feature, shape, and size: We’re square, or round, of brass or iron made, Sometimes of wood, yet useful found in trade ; But, to conclude, for all our daily pains, We by the neck are often hung in chains. Either we're equal or one is greate...

Story: Three guys A, B and C meet daily to play frisbee. They determined: Always if A doesn't have a frisbee, then B has one. If B doesn't take along a frisbee, then C has one. Today B hasn't a frisbee. Question: Which boys have a frisbee today?

Two friends are discussing concepts for a new fantasy story: A: There exists a magical mirror that leads to a mirrored universe. In this universe, people drive on the left side of the road, and you were a king who was adored by everyone! Unfortunately, you from that universe died in an accide...

And fill with right Mathematical operands and enjoy. Six Relations shown in the pictures are missing the right operands. You can only use plus, minus, multiplication, division signs in between the sixes. Operations are carried out from left to right.

This is a 9x9 grid, with a sign in the center cell like shown. You can add signs to this grid one at a time following these rules: Each sign placed must point to the next sign placed Placed signs become obstacles, so future signs cannot point through them Every new sign turns right (90 deg c...

The objective is to enter the numbers 1,2,3,4,5,6,7,8,9,10 in the blue circles. Doing this, the sum of the numbers has to be equal in the three connected rectangles (a rectangle consists of 4 connected circles, my painting skills aren't the best) ! Also, try to determine the smallest pos...

I need help with this riddle: What do you call people who repair your vehicles and jump out to scare you? It's 2 words and "we don't call them that and we think they're quite ethical."

Five cars are driving in a roundabout traffic at the same moment. Each comes from an other direction, and drives less than one full round. Also each car leave the roundabout traffic in an other direction. Question: How many possible combinations are there for the cars to leave the round...

Move two matchsticks to make 2 E's. (The Matchsticks cannot be stacked onto each other).