On the isle of Uauau

On the isle of Uauau the natives speak the truth on one day and lie on the next. On his or her “truth-day”, the man or woman will always speak the truth, and on their “lie-days” they will always lie. As a further complication, their truth days and lie-days are not synchronized, what is a truth day for one of them can be a lie day for his neighbor, father, brother or friend.

1) Today is a truth-day for me^*/*****
You meet a native who says: “Today is my truth day”. Can you conclude if he has a truth-day or not?

You can check your solutions here

2) Yesterday^*/*****
On Friday you meet a native who tells you: “Thursday is one of my lie-days”. Can you conclude if the native is speaking the truth or not?

You can check your solutions here

3) Different truth-days^**/*****
You meet two natives. One of them tells you:
“My friend and I have different Truth-days. Today is my friend’s lie-day.”
Does at least one of them have a lie-day?

You can check your solutions here

4) Friday(1)^***/*****
You meet two natives, let’s call them A and B as their real names are hard to pronounce. A says:
(1) My friend and I have the same truth-days.
(2) Last Friday my friend had a lie-day.
Does A speak the truth?

You can check your solutions here

5) Friday(2)^***/*****
You meet two natives on a Friday. For a change, let’s call them A and B, as their names are hard to remember. A says:
Yesterday I would have said that Friday is B’s truth-day.
Does B have a truth-day today?

You can check your solutions here

What comes next?

what comes next?^****/*****
1, 1, 2, 5, 12, 35, 108, …

You can check both your solutions 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.

Nonogram

Sanders, the most innovative puzzle magazine publisher in my native Netherlands, recently published a new variation of Nonogram, also referred to as Hanjies, grid puzzles, picross or, in Dutch, Japanese Puzzles (Japanse puzzels).

It uses triangular grids instead of the customary square grids, which adds a nice touch to this puzzle type. This puzzle type is sometimes called Triddlers, and comes in two types:
(a) the triangles are the half of a square.
(b) These triangles are equilateral triangles, with 60 degrees in every corner.
The puzzles in this publication arte of the latter type, which I much prefer. A nice feature is the inclusion of a small puzzle alongside a big one on every page. Well recommended!
You may wish to try to obtain one through their webshop, I just discovered they now ship internationally.

(Apologies for not including a sample puzzle this post, I havent yet discovered good tools for making good triangular or hexagonal grids. Tips are appreciated, plz add them in the remarks section)

Bongard problem 34

The Russian scientist M.M. Bongard published a book in 1967 that contains 100 problems. Each problem consists of 12 small boxes: six boxes on the left and six on the right. Each of the six boxes on the left conform to a certain rule. Each and every box on the right contradicts this rule. Your task, of course, is to figure out the rule.

Bongard problem 34^**/*****

You can check your solutions here

You can find more Bongard problems here and at Harry Foundalis site, and in the category ‘Bongard problems’ in the right margin of this page.

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 5 stars.