Snow
This morning, there was a thin layer of snow on the ground, so thin that it did not cover
everything. I did not notice it immediately. During the day
the temperature remained below zero degrees Celsius
and there was a moderate wind from the East.
Richard Guy
This morning, I received an email from Richard Guy about some
of the interger sequences that I
contributed to On-Line Encyclopedia of Integer Sequences. He was interested
in the recurrence equations for the sequences
A003696,
A003733, and
A139400.
I answered him that the first two can be found on
the page "Results of counting specific
spanning subgraphs of the graphs G x P_n" (which is part of
the page "Counting Hamilton cycles in product graphs"),
namely here and here.
The third sequence, that was entered by Paul Raff, does give a recurrence equation but not all of the initial 32 terms
that are needed to define all terms. I compiled the counting program and calculated the first 100 terms and also
included the matrix in the output. The recurrence equation is related
to the eigen-polynomial of the matrix. He also asked if the paper
"On the number of specific spanning subgraphs of the graphs
G x Pn" was published and if he could
get a preprint. I send him the link to an earlier
version of the paper.
I also asked him, if he could send a link to his home page.
Only in the afternoon, I discovered that
Richard Guy
is quite a famous mathematician. I am happy that I could make
a contribution to his research into divisibility sequences.
Neil Sloan
Yesterday evening, I got an email from
Neil Sloan,
who is the maintainer of the On-Line Encyclopedia of Integer Sequences (OEIS). Through an
email from Richard Guy he became aware
of the page Results of counting
specific spanning subgraphs of the graphs G x P_n. I already
had submitted many sequences from that page to the OEIS. He was
unaware that many of the sequences where published in a paper.
The rest of the evening I spend writing a detailed answer to
his enquiries. This morning, I got a reply from him. He has
added the missing sequences to the OEIS and also included the
recurrence equations. Some of which are now among the largest in the database.
He also send me a list of corrections to my pages. I promised
him to over these and also check all the sequences that added.
I think that the OEIS is a great means for bringing mathematicians
together, because for many mathematical problems it is possible to
derive a interger sequence and by searching for the sequence
in the OEIS it is possible to find others working on the same
problem, or even discover interesting relationships between
mathematical problems that are widely apart.
This evening, I had some trouble entering the campus of the
university. There was a soccer-match going on between
FC Twente and NAC Breda and some police agent
waved me to the right just before I wanted to go under
the bridge which leads to the round-about at the entrance
of the campus. I almost hit a person on a bike when I turned
to the left, but I could brake just in time. In fact, I was
already unconsiously braking, when I turned. A little further
I made a U-turn and through another road, I arrived at the
round-about and could enter the campus without problem. I
still don't understand why I could not go under the bridge.
When I arrived, Rudi and Huub were already playing a
game of Go. I watched
their game, and when they finished, Rudi suggested I should
play against him. We agreed on a four stone handicap for me.
But already soon, I felt lost, and not being able to win the
game, and by playing some silly moves, I only made things
worse. At one point, Rudi encouraged me to continue when I
thought about resigning. But when I for the second time,
lost some stones, I resigned. If I would not have lost those
stones, I still would have lost. Rudi and Huub analyzed the
game, while I just watched them. In a certain sense Huub is
really stronger than I. I am not even going to bother about
trying to reconstruct the game record this time.
Bookcase
This afternoon, I spend some time to fill the new bookcase
besides my bed. I placed the second bookcase last Saturday,
besides the first. I am already thinking about placing a
third bookcase beside my bed. After I finished placing the
books, I took a picture. The two top shelves are filled with
my diaries from right to left.
The second shelve of the right bookcase has my most beloved
novels. The fourth shelve is filled with books that I
still have to read. The second shelve of the left bookcase
has more novels and books I like. The third shelve has
bibles and christian literature. The fourth shelve has
games and DVD's.
Some light snow
This morning, there was some snow
on the grass in our back garden. When I left to my office,
it started to snow, and it kept on snowing for about an
hour. The snow stayed on about half of the surface area
of the ground. Through the day, the snow disappeared.
Wet wet snow
This afternoon, we had some wet wet snow falling from the ski. It was already wet, when
it was falling down, and would leave no trace on the ground.
Today, came the news that Geert Wilders has
been refused entry to the United Kingdom.
He wanted to London on Thursday, but today he received a
letter telling that he was not welcome, because his visit
constitute a threat to public order. He still want to go.
Dutch Ministers are quite upset about this.
Ernst Hirsch Ballin, the Minister of Justice, told his British
colleague Jacqui Smith that people of the parlement should
be free to express their thoughts. However, it is also this
Minister who suggested that the constitution should be
changed such that insulting a certain faith would be
equivalent with insulting its believers. (He is also the
one who caused Gregorius Nekschot to be arrested.) It is this same
idea that is found in the
court decision to order the prosecution of Geert Wilders.
And it is this prosecution that probably played a role
in the decision of the government of the United Kingdom
to refuse Wilders, or at least a way to justify it. It seems
that freedom of speech is rapidly disappearing in Europe.
Wet snow
When I left for home this afternoon, I noticed that it
was snowing. At first I thought
it was just the kind of wet snow we also had yesterday,
but the closer I came to home, the more white patches
I saw on the ground (mainly on the grass). So the snow
was not as wet as it seemed. Still I would classify it
as wet snow.
This evening, I was shortly after nine that I arrived
at the university to play Go. I
was a little surprised to find only Rudi, who was about
to leave for home soon, if I would not arrived. We
agreed on a seven stone handicap for him. About half way
the game, when I was already getting behind, Huub arrived,
and he followed our game play. We did play a Ko during
the end game, but it was kind of useless, because I lost
with 40 against 52points. We analyzed the game till
and when I arrived at home, I tried to remember the
game and came up with a game
record. Huub will send me some pictures he took,
so maybe I will be able to extend the record a little
further.
Geert Wilders
I am a little surprised that in the British press
Geert Wilders is described by terms like
"far right", "someone in the margin of extreme right", and
"populist twit and bigot" and said to encourage
extremism. I wonder whether these people realize
that about 15% of the Dutch are supporting his party
(PVV) at the moment (according to
a recognized popularity poll)
which is barely less than the Dutch Labour party (PvdA)
would get. It also makes it the third largest party of the
nine parties that where elected into the parlement.
Support for Wilders grew substantial after
a court ruled that he should
be prosecuted. Furthermore, it should be noted that
much larger part of the population worries about the
slow but steady islamizations of the society and the
restrictions on the freedom of speech that seem to be
caused (directly or indirectly) by the muslim minority.
This is supported by the fact that 50% against 46% of
the population feels that Wilders should not be prosecuted.
The whole day there was wet snow
falling from the sky sometimes mixed with some rain.
Around four o'clock the sun started to shine, but a
quarter of an hour later it was dark outside and it
looked like there was some fog, but it was just snow.
Going into the city
Around one o'clock Li-Xia and
I went into the city. She gave me a little scare, when
she turned left just before an approaching car.
After we parked our bike, I bought a currant bun
from Bakkerij 't Stoepje.
Next I bough some Soggus rye bread from
Bakkerij Verbeek.
We talked a little at Gallerie Beeld en Aambeeld. I heard that the paintings
by Billy Foley are still
at the Faculty Club at the university.
At the De Slegte bookshop
I first bought the following three books for 10 Euro:
We walked around a little more and at 15:07, I bought the book
Lover of loser, your choice for € 8.50 by Carry Slee as a
present for Annabel.
Next we went to bookshop Broekhuis,
where went to get a free CD for a ticket which I got
when I bought the book Maak jezelf maar klaar by
Elsbeth Etty on January 5, 2009. Because I could not
make a decision, Li-Xia selected a CD with
Symphony No. 9 by Beethoven. We walked back to
market, where I bough another currant bun and
490 gram of bean sprouts. Then we went int the
department store V&D where I bought a tiny
dictionary with the title Drop je lyrics 2 about
teenage slang for two euro. On the way home, I
bought some fresh tofu. We did some groceries and arrived home
around four o'clock.
Snowbow?
When we left church, about half past twelve, there was
some snow falling from the sky and the sun was shining
through some thin clouds. I immediately made some
remark about a snowbow in the sky, although I knew that
such a thing does not exist. It kept on snowing on and off
during the afternoon, but it was only at the end of the
afternoon that some of the snow stayed on the ground.
Sexism
According to this article, men really do see women as 'objects'.
Professor Susan Fiske
reports the discovery that when men look to half naked women
a part of their brain becomes active that usually reacts to
objects and that some other part, that is involved in social
interactions gets deactivated. This effect seems to be
stronger in men with sexist tendencies. But can one really
draw any conclusion about whether men truely, literally see
women as objects in these circumstances? Susan Fiske
states: "They are not treating them as fully three dimensional
humans." But it would not surprise me if the part of the brain
that is active when viewing objects, is very much involved
with seeing three dimensional. I have noticed for a long time
that I can somehow switch between two dimensional viewing and
three dimensional viewing. Three dimensional viewing takes
much more energy and is involved into construction a three
dimensional volumen representation of an object (or human
body for that matter). It already has been known for a long
time that men do take measurements of female bodies as part
of their evaluation of a womens attractiveness. Furthermore,
she suggest that seeing a lot of "sexualised images of young
women" causes men to see women more as objects. I am getting
the wierd feeling that this line of thought is rather sexist
and cannot be confirmed by her finding. She could only make
that conclusion when she would have compared men from different
types of societies. I really doubt if a significant difference
would be found.
Playing Go
This evening, I went to the university to play Go. I was the first one to arrive. Not much later
Huub arived. Rudi had told us last week that he probably
would not make it. We decided on a game where he would get
two stones ahead. Somewhere in the middle, I played a little
to hasty in the excitement of the game, and allowed him to
connect a group of stones that otherwise might have been
dead. Go is not only a game of thinking, but also of being
able to control oneself. In the end game, I also made a
pretty big mistake, and lost a whole group of stones. At
that point I resigned, but we continued playing. I lost
with 43 again 15, I am not mistaken. We replayed only a
small part of the game.
More (wet) snow
This morning, when I looked at the Dutch rainfall radar, it indicated that there
was precipitation in our area. When I looked outside,
I did not see any signs of rain. This sometimes happens
that the rainfall radar gives a false positive. But when
went outside, I noticed some small white snow flakes falling from the sky. It even got a little
stronger when I biked to my office. But non of the snow stayed
on the ground. In the afternoon we got some more snow, which at
someplaces did stay on the ground. It surprise me that
we just keep on getting this kind of wet snow.
Tornado
Yesterday evening, I spend some time constructing
a KML file
with Google Earth
about a F3 tornado that occured in the Netherlands
on June 25, 1967 based on information I found on
a web page of
the Royal Netherlands Meteorological Institute.
I heard about this tornado through the book
Maak jezelf maar klaar by Elsbeth Etty
which I am reading at the
moment. The book contains a fictional diary written in
the year 1967 and for this reason it frequently
makes references to historical events that took
place in that year.
Alzheimer's related to liver?
According to the press release New Study Provides Insight Into
Ways Organ Systems Outside the Brain May Affect Alzheimer's
Disease (related to the scientic article
Peripheral Amyloid-b Levels
Regulate Amyloid-b Clearance
from the Central Nervous System) there seems to be
a connection between the functioning of the liver and
Alzheimer's disease.
I find this information quite interessing and worthy to
investigate further.
The Powned betting game
In the Netherlands anybody who can collect enough members
can start a subsidized public broadcasting company.
The people from the popular blog Geenstijl (styleless), who contributed to
the resignation of Ella Volgelaar, Integration and Housing Minister
last year, are now planning the start op Powned. They have to get 50,000 paying members by
April 1, 2009. At the moment they have 33,407 members
and with the current progress it is not very likely they
will make the required number of members. To become a
member you have to donate € 5,72 (which, before
the Euro was introduced, was equal to 10 Dutch guilders).
They promised to return the donation plus 25 cents
(€ 5,98) in case they will not make it. This
makes, what I would call, the "Powned betting game". The
question is, what is the right moment to become a member
to make a profit out of it.
Because of the Darwin year some orthodox christians thought it
was a good idea to distribute
a bible tract among all Dutch households to
explain that evolution has not been proven and
that creation is a viable option. When some people heard
about these plans, they started a campain to return
the tracts to the sender and opened
a website
with the title (in Dutch) "Back to your maker". I
find it strange that some people have such a problem
with receiving such a tract through the mail, as they
receive loads of advertizements every day. There were
even some people sending death threats. I know, these
should not be taken so seriously, but still I find it
strange. According to a poll: 19% of the Dutch do not believe that evolution
is a valid theory. To me evolution seems to be a more
valid (scientifical) theory that the idea of creation
in six days about 6000 years ago. Most people do not
realize that the greatest theological problem with
evolution is that it contradicts with the idea of
the fallen men, and thus cancels the need for a Saviour.
Still, I find the idea of a God that sacrifices Himself
as way to save people, a very attractive and genuine thought.
Evolution does not explain subjective consciousness or
reduces it to mere imagination ("I am only self-conscious
when I think about it"). Evolution theory does not
cancel moral law. Moral law could have arisen from
evolution, because it enables cooperation among primary
selfish individuals, in case when cooperation increases
the reproduction rate of those who cooperate. However,
evolution theory by no means is an answer to
the two big questions.
Encyclopedia
Shortly before four o'clock in the afternoon,
Li-Xia and I left for the city.
When we parked our bikes outside bookshop "De Slegte", we saw a sign saying that they
where sellings encyclopedia's for ten Euro. On the second
floor we found a Grote Spectrum Encyclopedie for ten Euro. I guess this
price is even less than the price the raw paper if you
would hand it in for recycling. I remember how I used to
page through this encyclopedia when I was in highschool.
(On marktplaats.nl
I found one being given away for free.) Li-Xia encouraged
me to buy it, but I felt that we did not really have a place
to put it. I did buy some other books. Three books in the 3
for € 10 category and one book about a woman with
a 52 year old husband being diagnosed with Alzheimer's Disease. The books are:
- Thee op de blauwe sofa (Tea on the blue sofa)
by Natasha Illum Berg.
- Twee dochter en een reiger by Martin Bril.
- Elvistranen by Bart Chabot
- Een jaar met duizend dagen (A year with 1000 days)
by Berit Degnæs.
While we were in the shop, my phone rang. It was
Annabel, who told me that she
would join us for dinner at Camel. At home, I started
to read A year with 1000 days.
This months interesting links
Home
| January 2009
| March 2009
| Random memories
Sunday, February 8, 2009