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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.

Saturday, August 19, 2017

Solution for 7 and 8

I worked on the program for the the Irregular Chocolate Bar puzzle and found (maybe all) solutions for sizes 7 and 8. The program found 56 solutions for size 7. Here are twelve of these solutions:
1 6 11 15 21 25 29 31 35 39 45 49 54 59
2 3 9 13 19 23 27 33 37 41 47 51 57 58
3 11 13 18 23 27 28 32 33 37 42 47 49 57
5 6 11 15 21 25 29 31 35 39 45 49 54 55
6 7 9 17 19 27 29 31 33 41 43 51 53 54
7 8 17 18 19 28 29 31 32 41 42 43 52 53
8 11 13 18 23 27 28 32 33 37 42 47 49 52
9 12 17 19 22 23 27 33 37 38 41 43 48 51
11 15 16 21 24 25 26 34 35 36 39 44 45 49
12 13 19 22 23 27 29 31 33 37 38 41 47 48
13 21 22 23 27 28 29 31 32 33 37 38 39 47
16 17 19 21 26 27 29 31 33 34 39 41 43 44
For size 8, only three solutions were found, whiche are:
2 17 25 32 37 38 47 52 53 58 67 68 73 80 88 103
11 25 26 29 31 41 44 46 59 61 64 74 76 79 80 94
17 23 25 32 37 38 47 52 53 58 67 68 73 80 82 88


Tuesday, August 15, 2017

Brain machine

This evening at TkkrLab, I put together the brain machine that I bought at SHA2017. I sat at our work bench and followed the instructions on my tablet. I did not follow the instructions to the letter. For example, I did not extend the wire to the battery holder, but soldered the wire directly on the contacts of the battery holder. I used some double sided tape to attach the battery holder to the pair of glasses. I used one of the tie wraps to attach the PCB to the pair of glasses. I did not use any glue or scotch tape. I might if I apply the decoration. Several members helped me with drilling the holes and finding things I needed. I was happy I managed to finish it in one evening and several people tried it out.

Monday, August 14, 2017

Tetem and Bookshop Broekhuis

This morning, I visited TETEM art space, where I watched the videos By way of other directions by Lou Mouw and Ars Electronica Sparks Residency - Anouk Wipprecht on “Agent Unicorn” EEG wearable. At the start of the afternoon, I visited Bookshop Broekhuis. At 13:05:48, I bought the CD Passaggio: Ludovico Einaudi by Lavinia Meijer for € 9.99 and at 13:11:41, I bought a Moleskin Van Gogh Sketchbook for € 7.25 with 50% off.


With respect to the Irregular Chocolate Bar puzzle, I wrote down the following proof:
    Theorem: Let S be a set of natural numbers that sum up to n.m and that can be partitioned into n sets such that each set sums up to m, than for any pair i1 and i2 in S such that i1+i2=m, it holds that S-{i1, i2} can always be partitioned into n-1 sets that each sum up to m.

    Proof: Assume that S-{i1, i2} cannot be partitioned, while S can be partioned, than in all partitions of S i1 and i2 must be in different sets. There must be a partitioning P1, P2, .. ,Pn such that P1 contains i1 and P2 contains i2. Let {i1, i3, .. ,ik} (with k>3) the set P1, than i3, .. ,ik sum up to m-i1, which by assumption is equal to i2. It is now possible to construct a partitioning P'1, P'2, .. ,Pn where P'2 equal P2 with i2 replaced by i3, .. ,ik and P'1 equal to {i1, i2}. It is clear that P'2, .. ,Pn is a partitioning of S-{i1, i2} such that each set sums up to m.

After some puzzling, I discovered that there is no similar theorem for each combination of i1, i2, and i3 in S that sum up to m. This follows from a counter example, where S = {39, 40, 41, 98, 100, 102, 159, 160, 161} with n=3 and m=300. In this example, it does not work for 98, 100, and 102, because {39, 40, 41, 159, 160, 161} cannot be divided in two sets that sum up to 300.


Sunday, August 13, 2017

Who Stole My Spear?

This morning, I finished reading Who Stole my Spear by Tim Samuels, which I started reading on July 24, after I bought it on July 22. I found this a very interesting book. The book states that although in our modern society men are still in the majorithy in the higher regions of society, the bare facts are that in many areas men on average fare worse than women. The author argues that men have a harder time dealing with our modern society, which diverts furhter and further from our ancestoral hunting and gathering style of living. This books writes about important issues that should get more attention, especially among young men, because man usually do not talk about these issues.

Saturday, August 12, 2017


Friday, August 11, 2017


Tuesday, August 8, 2017


At the end of the afternoon, I returned from SHA2017 hacker camp, where I went to with some people from TkkrLab. This is the first time I went to such a camp and I had a great time. In the evening the camp was like an open-air disco with music and lightshows everywhere. One evening there was an event on the camp with home built vehicles, including riding pieces of furniture and also a KarTent on weels. I wrote two more badge apps: One for upcoming events (based on code from Event Schedule) and one named FFAA5E for setting random 'orange' pixels on the Pixelflut LED wall. Sunday morning, I bought the brain machine from Mitch Altman. I was a parking angle and did six shift with a total of about sixteen hours for which I was rewarded with meal vouchers and allowed me to enjoy the fantastic (mostly vegaterian) meals cooked for the volunteers. Notable talks I attended are:

Wednesday, August 2, 2017


At 15:09, I bought the book Groninger Museummagazine. Jaargang 27, no 1 edited by Steven Kolsteren, Willemein Bouwers, and Rudo Menge, written in Dutch and published by Groninger Museum in 2014 from charity shop Het Goed for € 0.50.

Monday, July 31, 2017

Valerian and the City of a Thousand Planets

In the evening, Annabel and I went to watch Valerian and the City of a Thousand Planets. We both enjoyed the movie and were drawn into it. The movie did get some average reviews, particular with respect the script being to simple. Yes, that might be true, but it did not really bother me, because there were lots of twist and creative ideas to compensate for it. I also liked the less obvious humor that you often find in American movies. I also feel that it stay true to the tone of the comics series Valérian and Laureline it is based on. I like the more organic type of science fiction. This first movie feels as the first of a long series of movies. I heard that Luc Besson already wrote two script for sequels. However, it is doubtful that this will happen, because the movie did not do well in the USA, which most likely because it was not based on an American comic series.

Saturday, July 29, 2017

First Python program

I wrote my first Python program, actually it is in MicroPython as adapted for the SHA2017 Badge. The program is an animation based on the first computer generated art works by Peter Struycken. I have uploaded (first version of) program to the Hatchery under P. Struycken. I am still going to adapt the program, because in the emulator I could not get the buttons to work.

Tuesday, July 25, 2017


At 10:26, I bought the book 25 buildings you should have seen edited by Maaike Behm and Maarten Kloos, written in English, Dutch, Spanish, and German, and published by ARCAW/Architectura & Natura Press in 2002, ISBN:9789076863078, from charity shop Het Goed for € 0.95.

Sunday, July 23, 2017


At Tetem art space, I watched a movie The Pack - Impressions from Our Family: Sixteen One Minute family albums Curacted by Felix Burger. Then I joined the workshop by Saskia Griepink. We were asked to help her with working a piece of art made from polyurethane insulation foam. We had to cut a thin slice of the foam and after having painted it, stick it some fresh foam.

Next I went to the opening of the exhibition of Emma Bijkerk and Kirsten Everink at Artikel 1 Overijssel. They both showed earlier work. In the early works of Emma, you can clearly recognize her latest works as shown on the AKI finals exhibition. Kirsten shows creamic works, while at the finals exhibition she showed only paintings. Some of the creamic works have been decorated with painting.

Saturday, July 22, 2017

The Hague

I went to RevSpace The Hague to help with the assembly of the SHA2017 badges. I worked on inserting the flexible cable from the e-ink display into a connector on the back of the PCB. This involved bending the cable into a U shape, opening the connector, inserting the cable, and closing the connector. The first took me about a minute, but when hours went by, it went faster and faster. I worked for about four hours at one of the four work stations. Next to use a team was working on flashing the software, glueing the display, and packaging the badge with display together with some additional LEDs, a vibration motor, a rechargable battery pack, and some other materials.

Afterwards, I went into the city center to look at some bookshops. At 17:07:26, I bought the book Who Stole My Spear? written by Tim Samuels in English and published by Random House in 2017, ISBN:9781784753368, from Van Stockum in The Hague for € 11.50. At 18:33, I bought the book Girl in a Band written by Kim Gordon in English and published by Faber & Faber, Limited in 2015, ISBN:9780571313839, from The American Book Center in The Hague for € 12.99.

Friday, July 21, 2017


At 17:43, I bought the following two books from charity shop Het Goed:
  • Sculptuur in Nijmegen edited by Felix Villanueva, written in Dutch and published by Gemeente Nijmegen in 1990, ISBN:9090034013, for € 2.95.
  • Restruimte: Het belang van dat wat er niet is written by Rinus Roelofs, Ed Brinksma, Dave Blank, and Martha J. Haveman, written in Dutch and English, and published by Qua Art - Qua Science in 2011 for € 0.95.

Thursday, July 20, 2017

AKI's serveertip

In the evening, I went to opening of AKI's serveertip exhibition with works from students that graduated from the AKI. I talked with: A picture by Paul Clason.

Friday, July 14, 2017


Tuesday, July 11, 2017


Sunday, July 9, 2017

Gerrit Rietveld Academie

I went to Amsterdam, where I arrived at the central station at eleven. I took some metro's and after I short walk, I arrived around a quarter to noon at the Gerrit Rietveld Academie to look at the finals exhibition of this year. I stayed there till four in the afternoon. I found the following students with their work worth mentioning (in the order that I encountered them):

Afterwards, I visited bookshop Het Martyrium for about a quarter of an hour before closing and Scheltema, where I looked around for about one and half hour without buying anything.

On the way how, I saw two sun dogs with a rainbow pattern. I took a picture. When I biked home from the railway station, the sky turned red and I stopped to take some pictures of which the last turned out to be the best.

Wednesday, July 5, 2017


August 2017
July 2017
Juni 2017
May 2017
April 2017
Alzheimer's Disease
Trip to China 2010
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