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I write, therefore I am

With this variation on a famous statement by the philosopher Descartes, I would like to express that the act of writing about what happens in my life is important to me.

Friday, June 23, 2017

AKI finals 2017

In the afternoon, I went to the AKI finals 2016 exhibition at the AKI. This year, the exhibition was only in the school building. I ran into Wim T. Schippers and talked a little with him while standing at an installation by Ole Nieling. I found the following artist interesting: At 18:31, I bought provocatie | provocation | 挑衅, the finals catalogue, for €15.00.

Wednesday, June 21, 2017

Smallest maximum

In the past days, I worked on a program for calculating solutions to the Irregular Chocolate Bar problem. I discovered that it is not difficult to find solutions with using large sets of numbers where the maximum number is as small as possible. This results in the following solutions:
  1. : 1
  2. : 1, 2, 3
  3. : 1, .., 6 except for 3
  4. : 1, .., 8
  5. : 1, .., 11 except for 6
  6. : 1, .., 15
  7. : 1, .., 29 except for 15
  8. : 1, .., 41 except for 21
  9. : 1, .., 71 except for 36
  10. : 1, .., 71 except for 36
  11. : 1, .., 235 except for 10
  12. : 1, .., 235 except for 10
  13. : 1, .., 849 except for 465
  14. : 1, .., 849 except for 465
  15. : 1, .., 849 except for 465
  16. : 1, .., 1201 except for 1081
Note that some of the solutions are the same, for example, for 13, 14 and 15. This is because 14 is equal to 2 times 7, which are already included for a bar that can be divided in 1 up to and including 13 groups. Furthermore, 2 and 7 are coprime, which might explain why there exists a division in seven parts for which each part can be divided in two smaller parts. The same true for 15, which is equal to 3 times 5. I have no proof if this hold in general, but it seems likely.

Finding solutions with the smallest set (of possibly larger) numbers, proved to be much harder. The method of just generating all sets, proved to be too slow. I next worked on an algorithm that would generate sets that would fit the largest number of divisions. These sets contains twice as many or one less number of numbers. But this did not get me much further. So far, I have found:

  1. : 1
  2. : 1 2 3
  3. : 1 2 4 5 6
  4. : 2 3 4 5 6 7 9
  5. : 2 3 4 5 7 8 9 10 12
  6. : 3 4 5 7 9 11 13 15 16 17 20
  7. : 16 17 19 21 26 27 29 31 33 34 39 41 43 44
  8. : 17 23 25 32 37 38 47 52 53 58 67 68 73 80 82 88
It is possible that for the last two solutions, there exist even better solution, with fewer number (thirteen and fiftheen), but even larger values.

Thursday, June 15, 2017

Irregular chocolate bar

Yesterday, I saw a photo strip by Ype & Ionica about an irregular chocolate bar, inspired by bar from Tony's Chocolonely, that could nevertheless be equally shared by 1, 2, 3, 4, 5, and 6 persons. I noticed that in their design there were two pairs of pieces with the same surface area and I wondered if there was also a solution with all different numbers. I also wondered, if the more generic mathematical puzzle: find the 'smallest' set of natural numbers such it can be divided in all manners up to a given n, had been addressed by someone. On a Dutch blog by Ionica Smeets, she reports that someone named Dic Sonneveld found a solution with all different numbers, namely: 8,10,11,12,13,14,16, 17, 18, 19, 20, and 22. She also mentioned that several people concluded that there is no solution with eleven pieces. I started to do some puzzling myself and also told a colleague about the puzzle. It is obvious that the numbers for a given n should be equal to or be a multiple of the Least common multiple (or LCM) of intergers upto and including n. My colleague and I found the following solutions:
  1. : 1. (1 times 1).
  2. : 1, 2, and 3. (3 times 2)
  3. : 1, 2, 4, 5, and 6. (3 times 6)
  4. : 1, 2, 3, 4, 5, 6, 7, and 8 or 2, 3, 4, 5, 6, 7, and 9. (3 times 12)
  5. : 1, 2, 3, 4, 5, 7, 8, 9, 10, and 11. (1 times 60)
  6. : 1, 4, 5, 7, 8, 9, 11, 12, 13, 15, 16, 19. (2 times 60)
He found the last solution, the others are mine, but he did find another alternative for 4. I report two solutions for that case, depending on the definition of 'smallest' set of natural numbers. The first solution contains eight numbers with 8 as the lowest value, while the second solution contains seven numbers, but with 9 as the lowest. He found another solution with seven numbers, meaning that even between solutions with the same number of numbers, we have to define some kind of relationship to define which is the smallest set. A (finite) set of (finite) natural numbers can be represented by a single natural number using a binary representation.

Link

Sunday, June 11, 2017

Swimming and sailing

This morning, I swam around the lake together with some other people. After having taken a shower, I went sailing with four others. We managed to return to the island with only a little use of the poles. The boats have an almost flat bottom and no keel, which makes them drift very easily, especially when there is not enough wind to make some speed. In the afternoon, I went sailing with two others. One of them jumped into the lake several times and pulled the boat while walking on the bottom of the lake. This weekend, I only played one game of Go, when Pepijn asked me to play against him. I lost with 50 against 16 points where I got nine stones ahead. But even then it is not too bad, because he is a Dan player and I also did not really concentrate a lot on the game. I did look at games being played. We also replayed the first of the 50 AlphaGo vs AlphaGo games till the start of the end game. It is a pitty that DeepMind/Google is going to decommission AlphaGo and not making it available anymore to be played against.


© Rudi Verhagen

Saturday, June 10, 2017

Peddling

This morning, three others and I spend about two hours traveling through Giethoorn by boat and using poles to push the boat forward. I did some reading and also slept for an hour. In the afternoon, the couple who arrived peddling was teaching others to peddle on their boards. I also gave it a try, being a little nervous because I did not have a spare pair of trousers in case I would fall in the water. At my first attempt to stand up-right, I dropped to my knees immediately as I felt unstable. I was instructed to place my feet a little further apart. On the second try, it worked a little better. I had to take a few deep breaths to calm my hardrate and stop my legs from trembling. When I started peddling, I noticed that the trembling returned, but slowly it got a little better. When a speedboat was approaching, I dropped to my knees before the waves arrived. I guess, I would need another hour to become comfortable enough to go on a longer trip.

The Boxer and the Goal Keeper

In the evening, I finished reading the book The Boxer and the Goal Keeper: Sartre Versus Camus by Andy Martin, which I started reading on May 19. I bought the book on Wednesday, March 9, 2016. I found this a well written and interesting to read book. The only problem I had with it, and which I have encountered with other biographic books, is the in some places thematic approach. The book definitely made me interested in reading more from and about both Sartre and Camus.

Friday, June 9, 2017

Kraggehuis

At the end of the afternoon, I arrived in Giethoorn. I had wait some time before the boat arrived to bring me to the Kraggehuis, a group accomodation in the middle of the lake. When the boat arrived, I had to wait a little more, because there were some last minute shoppings to be done. The boat had no engine, so we needed to used long poles to push is forward, because the water is less than a meter deep. Some people were playing Go outside when we arrived at the island. Dinner was served around eight in the evening, just after a couple arrived peddling on 13'2 Explorer boards. I looked at several Go games being played by others.

Thursday, June 8, 2017

GOGBOT café

This evening, I went to the GOGBOT café event at Tetem art space. There were presentations by:

Tuesday, June 6, 2017

Link

Thursday, June 1, 2017

Book

At 17:54, I bought the book AKI Eindexamencatalogus studiejaar 1987/1988 written in Dutch and published by Instituut voor Hoger Beeldend Kunstonderwijs in 1988 from charity shop Het Goed for € 3.95.

Link

Monday, May 29, 2017

Link

Sunday, May 28, 2017

Bookshops in Utrecht

From the railway station, I walked through the streets Voor Clarenburg and Mariastraat to bookshop De Wijze Kater. I just paid a short visit and only looked at some singing bowls. Next I went to bookshop Steven Sterk and spend some time looking around. At last, I visited Broese Boekverkopers. There again, I only looked around.

Saturday, May 27, 2017

Rob Scholte

I went to the lunch interview/discussion with Rob Scholte about his work on the How on earth should this be art exhibition at Concordia in Enschede. There were also some young ladies who were studying to be art teachers, who raised some interesting questions. Afterwards, I shortly talked with Rob Scholte and discovered that he knows Peter Struycken as well.

Friday, May 26, 2017

An announcement move

Yesterday, I got up early again, and watched the second Go match between Ke Jie and AlphaGo. Ke Jie played an almost perfect game for the first hunderd moves (according to the winning chance calculations of AlphaGo). Afterwards Ke Jie told that he was taken over by his emotions in the second half of the game, after a very complex situation had been created on the board, what I would describe as total go, where all the stones on the board where somehow connected and involved in the fight. At some point there were eight unsettled groups, which is an unheard of high number. Ke Jie, quit suddenly it seemed, resigned at the start of the end game. He must have concluded that his position was hopeless.

Today, I did not get up early, and when I opened the live channel, it was at the start of the end game between AlphaGo and five Chinese professional players. I did not follow the game in great detail. But suddenly, I heard the two female commentators calling a move of AlphaGo "an announcement move". When, I noticed that AlphaGo had played an empty triangle move, a had to laugh out loud. All beginners are being told that the empty triangle is a very bad shape and that if they could simple avoid playing it, they would immediately jump in strength. It is a move with which AlphaGo says: I am so sure of my victory and I just play a very stupid move to let you know. About three minutes later, the team of Chinese professionals, resigned. Of course, AlphaGo did not play this move with the suggested intention. Actually, it is not able to internally verbalize such reasoning, let alone do it on purpose. AlphaGo is trained to maximize its chance of winning, not to win with the largest possible margin, which means that if it is ahead with more than the smallest possible margin for winning, it starts to play moves to reduce the margin if those moves according to many Monte Carlo playouts give a higher win chance. When we humans, who are not able to perform all those thousands of playouts, have to learn a game like go, we do this by verbalizing all kinds of rule of thump. Some are simple and others are had to grasp. We find enjoyment in grasping the rules, in getting a deep grasp of the game. This immediatly shows the big difference between deep learning networks like the one used in AlphaGo and our minds. In our brains there are neural networks with similar or even more powerful capabilities, but they mostly implement unconscious data processing. We can pick a familiar face out of a crowd in a blink of a second, sometimes we even have to search with our eyes to find the face to affirm it was indeed someone we know. We play games like go primarily with the more higher, more conscious parts of our brain.

Link

Tuesday, May 23, 2017

The Future of Go Summit, Match One: Ke Jie & AlphaGo

I had set my alarm at four in the morning. Shortly after half past four, I started followeing The Future of Go Summit, Match One: Ke Jie & AlphaGo when the first two moves had been played. I set my Go board on just left of the keyboard and copied the moves being played. I shortly followed the Chinese commentary, but could not make sense of it. It was nice for Haylee to do the second hour of commentaries. Shortly after six o'clock, LIVE AlphaGo [W] vs. Ke Jie 9p [B], Round 1: Commentary by Myungwan Kim 9p came on. I followed it a bit, until they started to replay the game from the start. Around 7:21, Myungwan Kim concluded that Kie Ji is about five points behind and that the game is coming to a close.

Sunday, May 21, 2017

Link

Thursday, May 18, 2017

Robotic Couture

I attended the opening of the exhibition Robotic Couture at TETEM art space. I arrived a little after five in the afternoon. It was not very busy. It took some time before Anouk Wipprecht held the opening speech, because she had to wait before a young lady was ready with putting on the robotic cocktail dress. Wipprecht spoke fast with a mixture of Dutch and English, not so strange, because she has been living in America for some years. She will stay in Enschede for the Maker Festival this weekend and give a talk on Saturday. I met several people from TkkrLab and looked around the exhibition. I did not consume one of the cocktails being produced by the cocktail dress.

Link

Wednesday, May 17, 2017

Book

At 17:44, I bought the book aki akademie voor beeldende kunst eindexamencatalogus 1994 edited by Bas Könning, Boris Veldhuyzen van Zanten, Marijke Harmens, and Gerhard van Dragt, written in Dutch and published by AKI in 1994, ISBN:9073025060, from charity shop Het Goed for € 2.50.

Tuesday, May 16, 2017

Introduction

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