Takuzu / Binairo

February 3, 2017Magazine puzzles, Pencil and Paper puzzlesTeun Spaans

Takuzu (often called Binairy/Binairo or occasionally Tic-Tac-Toe) puzzles have been around for several years. In my native Netherlands they have been published by both Sanders puzzles and by Denksport, and also in daily newspaper Algemeen Dagblad.
In France, they have been published under the name Takuzu in le Figaro, at least in 2011.

The puzzle consists of a rectangle or square with an even number of rows and columns. This is partly filled with 0’s and 1’s. It should be completed by the solver with 0’s and 1’s in such a way that:
a} There are never more than two consecutive 0’s or 1’s in any row or column;
b) There are an equal number of 0’s and 1’s in every row and column;
c) All rows and columns are different;
This last condition seems to be rarely used in the commercial publications. Sizes are usually 10×10, 12×12 or 14×14, though 6×6 and 8×8 are often offered as introduction puzzles.

Example 1:

puzzle 1: 6×6:^***/*****

puzzle 2: 7×7:^***/*****

You can check your solutions here and here

New puzzles are published at least twice a month on Friday. Solutions are published after one or more weeks. You are welcome to remark on the difficulty level of the puzzles, discuss alternate solutions, and so on. Puzzles are rated on a scale of 1 to 5 stars.

Flags (1)

January 27, 2017Inductive reasoningTeun Spaans

Flags of countries (1)^{***/*****

Look at these flags:}

Which of the following three flags belongs in the above group:
a)

You can check your solutions here

Cryptarithm

January 20, 2017CryptarithmTeun Spaans

This weeks puzzle comes from “Quark special”, a Japanese puzzle booklet or magazine that I once obtained through the late Nob Yoshigahara.

You can check your solutions here

Matchsticks – a list of apps

January 13, 2017MatchsticksTeun Spaans

Recently I downloaded a couple of matchstick puzzle apps on my android phone and on my ipad. Below you find an incomplete list of android apps with matchstick puzzles.

Here is a short list:

Name	Publisher	Type of puzzles	Remarks
Matchstick puzzle	Uysal Mehmet	Digital Puzzles	Minimalistic interface. It baffled me at first. I didn’t see hints or solutions, but that doesn’t mean they aren’t hidden somewhere.
Puzzles with matches	Celtic Spear	Digital matches, triangles and squares	Well designed interface. Puzzles gradually increase in difficulty. Recommended!
Matchstick puzzles	Gamophonica	Squares	At level 6, I found a symmetrical solution is not recognized. Interface is clear. Same on levels 7 & 8, and probably on subsequent levels too. I informed the publisher and they responded quickly to my email, so I trust this problem will be resolved when you read this (written dec 2016).
Matches Puzzle Game	Bojan Klabjan	Squares, triangles, numerical digits	Original interface. Well designed. Recommended!
Matchstick Puzzle	Alt-y	Digital numbers	Both moving and 1 and 2 matchsticks.
Amazing matchsticks	Network Game&utility	?	I skipped this one, as it asked 4 types of access which I deemed unnecessary
Matches Puzzle 2016	Fitapp Inc	Digital numbers	Both 1 and 2 matches to be moved. If you are stuck, solutions can be bought with in-game money.
Math puzzle with sticks	LogiGames	Digital numbers	Beautiful interface, but I miss a clear indication of how many matches I have to move. Or maybe it is always just 1 match.

I admit I’m not even halfway through the list.

Anyway, here are two puzzles.
Problem 1^*/*****

Problem 1^***/*****

You can check your solutions here and here

Ages

January 6, 2017Ages, dates and time, ArithmeticTeun Spaans

Ages^**/*****

Ages^**/*****
A man is 25 years old and his wife 23. He noticed that the sum of their ages (25+23=48) is exactly 4 times the sum of the digits of their ages. (2+5+2+3=12).

When will the sum of their ages be exactly 8 times the sum of the digits of their ages? And when will it be 9 times the sum of the digits?

You can check your solutions here

Find a 4 digit number

December 30, 2016NumbersTeun Spaans

Number^**/*****
Find a four digit number abcd such that
– abcd is a prime number,
– a+b+c+d = 10,
– the sum of the digits of ab*cd equals 7.

You can check your solutions here.

On the first day of Christmas…

December 23, 2016CountingTeun Spaans

1) On the first day of Christmas^**/*****
On the first day of Christmas, my true love brought to me:
On the first day of Christmas
My true love gave to me
A partridge in a pear tree

On the second day of Christmas
My true love gave to me
Two turtle doves
And a partridge in a pear tree

Thus go the first two couplets of a traditional Christmas song. Question is:
Haw many things did my true love give me over these 12 days? (counting the partridge in the pear tree as one item)

You can check your solutions here

2) On the second day of Christmas^**/*****
Yeah, in puzzle 1 above you had the classical song. But in puzzle land, everything is different.
In puzzle land, on the second day of Christmas my true love brought me this puzzle:

“This puzzle consists of @ letters”

With what number (spelled out, of course) should @ be replaced to be true?

You can check your solutions here

3) On the third day of Christmas^**/*****
On the third day of Christmas, my true love brought to me this puzzle:

“This puzzle consists of @ vowels and # consonants”

Again, by which numbers, spelled out, should @ and # be replaced to yield a true sentence? Please note that “y” is counted as a vowel.

You can check your solutions here

Christmas puzzle

December 16, 2016Logicaivd, BrainteasersTeun Spaans

The Dutch equivalent of the CIA & NSA is called the AIVD. One of their departments has been compiling a set of Christmas puzzles for decades, and since a few years these puzzles are published on the internet. You can download the 2016 version.

Though most puzzles are language dependent (in Dutch), there are some which at least on the surface do not seem to require knowledge of the Dutch language.
Here is a list of the exercises and the translation of the exercises/hints of the puzzles for which you probably don’t need to know dutch:
2. Elementary: Which one is out of order?
4. What is the next number in each of the two series?
10. Two persons on a ferry are comparing two rows. One counts differences, the other comparisons. They arrive at the following series. What are the next numbers?
23. Sequences. What are the next three items in the lists?
I warn you, they have the reputation to be pretty tough. 100 points can be earned each year. Every year, people crack all exercises, but in no year did one person all problems.

Thanks to our daughter Joella, who solved puzzle 1b, I can offer you the puzzle below. Which number should replace the question mark:
?
position
drawback
frazzled
bragging
phishing
eternity
sickness

No, I don’t intend to publish the solutions. But I guess the solutions will be published here

cryptarithm: worship

December 9, 2016alphametic, CryptarithmBrainteaser, cryptarithmTeun Spaans

Alphametic^**
This weeks puzzle has a christian theme. In this alphametic, replace every letter with a digit. The same letter always represents the same digit and identical digits have always been replaced by the same letter:

You can check your solutions here

New puzzles are published at least twice a month on Fridays. Solutions are published after one or more weeks. You are welcome to remark on the difficulty level of the puzzles, discuss alternate solutions, and so on. Puzzles are rated on a scale of 1 to three stars.

The anchor puzzles

November 25, 2016TangramTeun Spaans

Starting in 1890, the German firm Richter produced a series of Tangram puzzles which were widely distributed during the First World War, or The Great War as it was then called, as a pastime for the troops in the trenches. With the pieces consisting of stone, they could survive in the horrible environment. They were used by both German and British troops.
The puzzles came together with sheets with exercises, which have been compiled by Jerry Slocum, one of the worlds greatest puzzle collectors. He published the exercises in a book, which you can order here. The firm stated that some of the problems have been contributed by the troops.
The anchor factories are now owned by Goki.

I recently purchased a series of anchor stone puzzles at internet-toys.com (Another supplier is http://www.padilly.com/brainteasers.html). Their delivery was speedy and accurate, and they have low prices. The puzzles arrived within a few days, though of course I can not vouch for delivery times in the rest of the world.
The puzzles are still made of stone, and below you find pictures of the once I obtained. Currently they do not offer the full range. The ones they do offer are in bright green, yellow, blue and red. The back of the cardboard boxes do mention Anker Steinbaukasten GmbH. There are no names of the individual cardboard boxes. Some of the boxes carry a number of puzzles on the inside of the box, some don’t. None had a solution, and the drawings on the cover do not match the inside arrangement of the pieces. This, the boxes state, is on purpose: no clue is given away. You did want to puzzle, did you?

There are 3 historical puzzles, which in “Puzzles old and new” by Jack Boterman and Jerry Slocums are called Zornbrecher, Wunderei / Ei des Columbus (I don’t see much difference between these two in their book) Herzratsel and Kreisratsel. These are the ones that come with the 10 exercises on the inside of the box.

The big surprise for me are the other puzzles: The do not seem to match any of the traditional Anker puzzles. At internet toys they are labelled maan, dennenboom, ster en kruis in Dutch, which translates into English as moon, pine, star, and cross.

Expect some exercises in the future with these new puzzles, though the usage of non rectangular shapes may cause some troubles in this endeavor. For the moment, here are the puzzles: