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More solutions for 7
In the evening, I worked on the program
for the the Irregular Chocolate Bar puzzle
and found more solutions for 7. Already some time ago, I started working on a
version of the program that iterates over all partitions for a given size,
such that the largest piece in each bucket is ordered from large to small and
such that inside each bucket the pieces are also ordered from large to small.
The idea is that by doing this, it is possible to avoid partitions that similar
to an earlier partition except with respect of the order of the pieces.
Furthermore, the algorithm has implemented a check to stop trying to construct
a partition when in some bucket the pieces are getting too small for it being
possible to divide the remaining buckets in the maximum number of pieces.
After I verified that this worked correct for sizes 5 and 6, I added a partial
knapsack algorithm, to check if a partial partition (for a given size) could
be used for all smaller divisions, in order to cut away large branches during
the generation that will never lead to a solution. When I ran this on size 7,
it found 210 solutions, which is much more than the 56 that I reported on
August 19, last year. Of these 210 solutions,
146 contain a piece of size 60. This means that there are 64 solutions that do
not contain a piece of size 60, which is 8 more than the earlier found 56
solutions. I still have to verified that all earlier found solutions are
included in the solutions found today, to rule out an error in the latest
algorithm. The first solution found (with a piece of size 60) is:
7 set: 1 3 8 9 13 19 23 33 37 47 51 57 59 60
4 buckets with 105: 51+13+33+8 60+3+23+19 59+9+37 1+57+47
5 buckets with 84: 57+19+8 51+33 60+1+23 47+37 59+3+9+13
6 buckets with 70: 59+3+8 51+19 37+33 47+23 57+13 60+1+9
7 buckets with 60: 33+19+8 37+23 47+13 51+9 57+3 59+1 60
More results for 8
I started the program for sizes 8 and 9. For 8 it found five more solutions,
besides the three already known solutions. All new solutions have a piece with
size 105. The solutions are given below. I also verified that all earlier
found solutions for 7 are included in the solutions that found yesterday.
6 9 10 21 25 36 41 49 56 64 69 71 84 95 99 105
6 9 21 25 26 36 41 49 56 64 69 71 79 84 99 105
1 10 14 25 29 41 44 49 56 61 64 76 79 91 95 105
4 11 25 26 31 41 44 46 59 61 64 74 76 79 94 105
1 14 25 29 34 41 44 49 56 61 64 71 76 79 91 105
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
At 12:04:08, I bought the book Mirrored Years written by
Diedrich Diederichsen, Midori Yamamura, and Lily van der Stokker, in English
published by Museum Boijmans Van Beuningen in 2009,
from bookshop Broekhuis for € 13.95.
At 20:24:37, I bought the book En liefde in mindere mate: dagboeken
1961-1987 written by Doeschka Meijsing in Dutch, edited by Ben Peperkamp
and Annette Portegies, and published by Singel Uitgeverijen in 2016,
ISBN:9789029539463, from bookshop Broekhuis
for € 17.50.
I got the book Gezien de feiten written by Griet Op de Beeck in Dutch
and published by Stichting Collectieve Propaganda van het Nederlandse Boek in
2018, ISBN:9789059654334, for free as part of the Boekenweek. Coming Sunday, I can also use it to travel by train
through the whole of the Netherlands.
Snow and cold
Yesterday there was some light snow during most of the afternoon, but it did
not stay on the ground, because the temperatures were too high. This morning,
there was some snow and some of it stayed on the ground. Temperatures are very
low for the time of the year. Two weeks ago, we also had a cold period. In both
cases the cause is the same: high pressure over Scandinavia that transports
cold air from the polar region to us. The maximum temperature at 2m was
-0.7° Celcsius and at 10cm it was -0.1° Celsius. It seems we have hit
record low temperatures today.
This afternoon, I ordered a Gigatron kit. On Friday, December 8 last
year, I went to a presentation about the
Gigatron TTL Color Computer.
I decided to use to Boekweek gift to go to Amsterdam. I
first went to bookshop Het Martyrium. At
13:05, I bought the book The Trip: Andy Warhol's Plastic Fantastic
Cross-Country Adventure written by Deborah Davis in English and published
by Simon and Schuster in 2015,
ISBN:9781476703510, for € 9.95.
Next I visited the Stedelijk Museum. I went to see the exhibition
The Collection: Stedelijk Base. I saw (among many others) the
Next I saw the exhibitions:
- Kitchen Gardens on Montmartre, 1887, by Vincent van Gogh
- La Montage Sainte-Victoire, ca 1888, by Paul Cézanne
- Femme dans un paysage, 1890-92, by Anna Boch
- Tableau no.3: Composition in Oval by Piet Mondriaan
- Tableau III: Composition in Oval by Piet Mondriaan
- Composition with Blue, Yellow, Red, Black, and Grey, 1923 by Piet Mondriaan
- Composition with Yellow, Red, Black, and Grey, 1920. by Piet Mondriaan
- Lozenge Composition with Two Lines, 1931, by Piet Mondriaan
- Cathedra, 1951, by Barnett Newman
- North Atlantic Light, 1977, by Willem de Kooning
- Rosy-Fingered Down at Louse Point, 1963, by Willem de Kooning
- Espaces Virtuels: Jaune et blanc, 1965, by Jesés Rafael Soto
- R 62-16, 1962, by Jan Schoonhoven
- Aggregration: One Thousand Boats Show, 1963 by Yayoi Kusama
- Art Must Be Beautiful, Artist Must Be Beautiful, by Marina Abramovic (only the last minutes)
- Windmolen, ca 1917, by Piet Mondriaan
- Clothing material, 1964, unknown
- 18A, Dec 02, 2002, 2002, by Peter Struycken
- 023, Dec 02, 2002, 2002, by Peter Struycken
- Radioaktiever Abfall, 1992, by Sigman Polke
- The Extinction of Feeling (HAL 15/91), 1991, by Peter Halley
At 14:58:09, I bought the book Art Sex Music written by
Cosey Fanni Tutti
in English and published by Faber & Faber in 2017,
ISBN:9780571328529, from Buchhandlung Walther Koenig at the Stedelijke Museum
for € 12.80.
Finally, I visited bookshop Scheltema for
about one and half hour. I did not buy a book.
At 11:00:10, I bought the book The Artist Interview: For Conservation and
Presentation of Contemporary Art, Guidelines and Practice edited by Lydia
Beerkens, written in English, and published by Jap Sam Books in 2012,
ISBN:9789490322328, from bookshop Broekhuis
for € 5.00. The book contains an interview with and some
reproductions of works by Peter Struycken.
This evening, just after I arrived from work, a package with the
Gigatron kit and the manual
Gigatron Assembly Manual written by Marcel van Kervinck and Walter
Belgers. I did not open the kit itself, but I have read parts of the manual.
This evening at TkkrLab, I started assmebling
(soldering) the Gigatron kit. I found back
my pair of scissors that I had lost on August
15. My plan with the assembling was to finish the first three steps after
I had checked the contents of the kit, but I already started with Step 4:
soldering the IC's. During the first step, two of the 40 capacitors dropped on
the ground and were temporarily lost. Below a picture of the state at the end
of evening. I plan on finishing the assembly on coming Saturday. During the evening, I also talked with Robert B. Lisek, who came to visit the space.
At 17:56:22, I bought the book Vreemdeling in een vreemd land written
Anson Heinlein, published by Bruna in 1973,
ISBN:9022990214, from charity shop Het Goed for
€ 0.50. It is the Dutch translation by M. Nicolaas-Lindeman and
J.E.A. Andriessen-van de Zande of Stranger in a Strange Land.
I finished reading the (auto)biography Vivienne
Westwood by Vivienne Westwood and Ian Kelly, which I started reading on January 31. When I bought the book, I had no idea who Vivienne Westwood was, but that was one
of the reasons to buy the book. I have not been dissapointed. It was an
At 12:24:12, I bought the book Positioning the art gallery: het Amsterdamse
galeriewezen in een internationale context edited by Noor Mertens and
Astrid Vorsterman with contributions from Jo Baer, Els Brinkman, and Peter
Mason, written in Dutch and English, and published by Valiz in 2012,
ISBN:9789078088394, from charity shop Het Goed
for € 1.50.
TkktLab Open Day
Today was TkkrLab open day from 11 in the
morning till four in the afternoon. Between showing vistors around, I finished
soldering the Gigatron mircocomputer, which
I started last Tuesday. After I did a final check, it worked
the first time when I powered it on. Later, I discovered that in the racing
game, the car does not start to drive. Maybe because one of the buttons of the
controller is not working, or I had not have it plugged in well enough. Or I
have to fix the soldering somewhere on the PCB.
Addition April 1: It seems I should have read the manual more carefull.
This months interesting links
| February 2018
| April 2018