PuzzlingInPython

by Victor Bryant

Published Sunday February 01 2026 (link)

Over the years I have used seven different PINs. The first consisted of a four-digit number (the first digit not being zero), and thereafter each new PIN was obtained by swapping over two of the digits of the previous PIN; each time this increased the PIN.

The first PIN (not surprisingly!) was divisible by 1, the second was divisible by 2, the third by 3, and so on, with the seventh divisible by 7 (in fact the seventh PIN was the only one divisible by 7).

What was the third PIN?

by Colin Vout

Published Sunday January 25 2026 (link)

]Rummaging through a cupboard I came across an old Snakes and Ladders set. The ladders (label them A to E) went from square 4 to 26, 18 to 28, 19 to 73, 22 to 60, and 41 to 98. The snakes (label them W to Z) went from square 53 to 24, 58 to 5, 72 to 33, and 90 to 66. For old times’ sake I couldn’t resist playing a game on my own. Starting from square 1, rolling the die and moving appropriately, travelling up ladders and down snakes when I chanced to land on their starting squares, I happened to finish exactly on square 100. The total of all the numbers I had thrown on the die was 51.

What was the order of all my up and down jumps? [Eg, A, Y, D]

by Mark Valentine

Published Sunday January 18 2026 (link)

Farmer Quentin keeps his prize bull in a circular field of diameter 50m. To improve the layout, he decides to switch to a square field with side length equal to the old diameter. He builds the new fencing around the old, with fence posts every metre starting at the corner. After completing the new fencing, he tethers the bull outside the fence to one of these fence posts with a rope of integer metre length, to allow the removal of the inner circular fence. As a result, the bull’s temporary roaming area is now four times what it was inside the circle.

What is the length of the rope?

by John Owen

Published Sunday January 11 2026 (link)

On my travels, I came across a group of some knights (always truthful) and some knaves (always lying). At first, I couldn’t tell which were knights and which were knaves. However, six individuals then gave the following statements about their group: “The number of knights is prime.” “The number of knights is odd.” “The number of knaves is square.” “The number of knaves is even.” “The total of knights and knaves is an odd number.” “There are more knaves than knights.”

These statements enabled me to deduce the composition of the group.

How many (a) knights and (b) knaves were in the group?

by Howard Williams

Published Sunday January 04 2026 (link)

My grandson likes making puzzles; his most recent one started with a four-digit number with all the digits different. He added up all the possible two-digit combinations of these four digits (eg, if the digits were 0, 1, 2 and 3 he would add 01+02+03+10+12+…). This total divided exactly into his four-digit number.

Not satisfied with this, he said he had added an extra digit (different from all the others) to the end of his number to make a five-digit number. The five-digit number was an exact multiple of the total of all the two-digit combinations of these five digits. He said that if he told me how many digits were in this multiple, I would be able to work out his five-digit number.

What was his five-digit number?

by Andrew Skidmore

Published Sunday December 28 2025 (link)

I recently attended a celebration with fewer than 100 family and friends. We sat round a large oval table with one seat for each person. I said to Liam that he could pick any seat, but it might be interesting to work out how many different arrangements were possible for people round the table. He replied “I’ll leave that to you Grandad”, then (mischievously) added “but remember I always sit next to you and to Granny”. The restriction that I must sit next to Liam divided the number of possible arrangements by a certain prime number. The further restriction that he must also be next to Granny caused further division by a prime number with a different number of digits.

What, in ascending order, are the number of people round the table and the two prime numbers?

by Peter Rowlett

Published Sunday December 21 2025 (link)

I offer my friends a bet: they pay £1 to play, then draw a card at random from a standard 52-card deck. If they draw the Queen of Hearts, I pay them a £30 prize, otherwise I keep their £1.

Although I have many friends, I have a reasonable chance of avoiding paying a prize. But I make a mistake! As I go around the group offering the bet to each friend, I forget to take their chosen card back and shuffle it into the deck, meaning each new bet is made with fewer cards. As a result, my chances of having to pay out are nearly 50 per cent greater. In fact if I had just one more friend, then my chances of having to pay out would be more than 50 per cent greater than if I hadn’t made the mistake.

How many friends did I have in the group?

by Peter Good

Published Sunday December 07 2025 (link)

Secret agent Robert Holmes was searching the hotel room of a foreign agent who was downstairs having breakfast. Holmes discovered a piece of paper containing the text DKCCVTCSZQRZYTAZXTTX and he thought this might be a coded message about the foreign agent’s mission so he sent it to his code-breaking experts.

They discovered that it was a message that had been scrambled by consistently replacing each letter of the alphabet with a different letter (no letter being used to replace more than one different letter). They decoded the message as a sentence containing four words, which they sent back to Holmes with spaces inserted between words. Holmes realised that his life was in imminent danger as soon as he read it.

What was the decoded message?