Weekend Cat Blogging: Alone in a sea

Alone in a sea of cardboard:

Another example of Luna's natural geometry set against hard artificial lines.

Vast expanses of fun…on what is otherwise a dreary Saturday for us here at CatSynth. But the extended weekend is a good excuse to complete the major projects remaining at CatSynth HQ.

The rain is actually good news this weekend for our former hometown of Santa Cruz – there has been a major wildfire in the mountains to the east. It's actually near Loma Prieta, for which the 1989 earthquake was named. Sadly, many people have lost homes in the mountains. It's a sparsely populated area, where people specifically chose to live and make their homes. Animal rescue has been a major and so far successful component of the effort, with horses and other animals being brought to the county fairgrounds near Watsonville.

We are also sad to hear about the passing of one of our Weekend Cat Blogging friends, Bonnie Underfoot. Please visit them and offer your thoughts.


Weekend Cat Blogging is being hosted by Kate and Puddy at A Byootaful Life. It looks like our favorite Luna look-a-like is having a birthday this weekend!

The Bad Kitty Cats Festival of Chaos and Carnival of the Cats, hosted by the Catboys Realm and the M-Cats club, respectively, are both dedicated this weekend to Bonnie Underfoot.

And as always, the Friday Ark is at the modulator.

Weekend Cat Blogging: High

Luna is way up on the ledge:

How high is it?

Rather high indeed:

One might even say “we couldn’t get much higher.” Perhaps this will earn us a ban, as it did for someone else in 1967.


Weekend Cat Blogging #156 is being hosted by Megan and the Bad Kitty Cats. Sadly, they are one fewer with the passing of one of the new kittens, Skimbleshanks. You can see a very sweet photo of him with Zed Monster.

The Bad Kitty Cats Festival of Chaos is elsewhere at Mind of Mog.

The Carnival of the Cats will be hosted this Sunday by the “cat boys” Kashim and Othello.

And of the Friday Ark is at the modulator.

Primary Highways: Oregon

Our series returns to the west coast, and to a state I know from personal experience. I have traveled through the western part of Oregon multiple times. It is a state that at first glance has much in common with northern California, politically and geographically, but has its own unique characteristics.

Traveling north on I-5, one crosses an arbitrary line the separates the spectacular landscape of far-northern California from the spectacular landscape of southwestern Oregon. The highway weaves through the mountains and valleys of the Cascade Range, including numerous volcanic (or formerly volcanic) peaks.

At the town of Medford, one can continue north, or take a detour east on state highway 62 to Crater Lake. Crater Lake fills a caldera in the Cascade Range, and is the deepest lake the United States. It's circular shape is quite distinctive, as are its internal landmarks, including Wizard Island (the pointy island to one side of the lake), the “Old Man of the Lake“, and several volcanic formations. I had the opportunity to visit Crater Lake many years ago.

More recently, I traveled the other route from Medford, on I-5 north to Portland, while I was on tour last October.

We experienced Portland's famously variable weather. Fortunately, many of the city's attractions are indoors. This includes Powell's Books. I could have spent the whole day in the Pearl Room, which contained the art and architecture offerings, as well as their extensive rare book collection.

Portland also has abundant public art. Across from Powell's is this “brush,” a noted landmark:


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This building brings to mind the city's nickname, Rose City.


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These are only a few of the photos I took while on tour. Please visit the original article for more images, including the intriguing “recursive elephant” sculpture (and the hidden cat).

Portland is someplace I could see living, and indeed the idea crossed my mind during my period of unemployment last year. Ironically, it was en route to Portland that I took the fateful phone call that led to my current job and new life in San Francisco.

We also performed in the coastal town of Astoria, which can be reached by traversing the coast range or traveling along the Columbia River on US 30. This is actually the western end of US 30, which starts at a junction with our friend US 101.


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Astoria was cool and rainy and very green, as one would expect along the northern Pacific coast. The people we met there were also very welcoming to a group of Bay Area musicians playing weird experimental music. Again, you can read more about our visit at the original tour article.

I have never been to the eastern part of Oregon, which is a very different place altogether. I am quite intrigued by the descriptions of part of eastern Oregon as a desert landscape. But it seems like one has to be very motivated to visit, as it is far less populated and less accessible via major highways. The east-west divide also seems to extend to politics, with western Oregon being more liberal in the “northern California” sense, and eastern Oregon being more conservative. I wonder how this divide is going to play, at least in the media, given the patterns of this election…

Weekend Cat Blogging: The Heat

The temperature hit 97F (35C) yesterday, which is exceptionally hot for San Francisco. Felt great to me, but it's a bit too much for the ketzela.

Here we see Luna trying to beat the heat resting under her new favorite table:

Even in the heat, she seems to have a sense of style. And fun. Note the cardboard furniture box to the left. Luna has always been fond of cardboard boxes, and this new one is no exception. Lots of fun for the teeth and claws, especially when you don't have to move far to reach it.

Like we said, this has been an exceptionally warm few days. It is famously cold and foggy during the summer months (June, July and August), though less so in our neighborhood. But it has been delightful to spend warm evenings out on the patio; and that “incipient warmth” in the morning, where the air still has a chill but one can feel it disappearing quickly. And with the energy of the city all around us…


It's never too hot for Weekend Cat Blogging, which is going on at Chey's Place.

The Bad Kitty Cats Festival of Chaos is returning home to the Bad Kitty Cats Journal this weekend.

The Carnival of Cats will be going up this Sunday at Artsy Catsy

And of course the Friday Ark is at the modulator.

Prime-counting function revisited

A couple of weeks ago we posted an article on “Calculus for Cats” and the Prime Number Theorem, which featured the, the prime-counting function π(x):

Basically, this function counts the number of primes less than or equal to a particular number. For example π(20) would be all the prime numbers less than 20: 2, 3, 5, 7, 11, 13, 17 and 19. So π(20) = 8.

So to calculate π(1000) would one have to literally count all the prime numbers less than 1000, including figuring out which numbers are prime? And what about π(1000000)? Unfortunately, the answer is yes.

Unfortunately, the answer is no, as Victor points out in the comments. Or more specifically, Victor's cat Blue Chip says “Neow!” I think is the point where one is supposed to say “my bad.” Victor is in fact V. S. Miller who co-authored the paper “Computing pi(x): The Meissel-Lehmer Method”.

The oldest method for computing π(x) is to use the sieve of Eratosthenes, which is literally counting all the primes below x. More efficient methods have existed for quite a while, notably astronomer E. D. F. Meissel found a method in the 1870s that he used to compute π(100,000,000) as 5,761,455; and π(1,000,000,000), though his result was found to be slightly off (too small by 56). It should be noted that Meissel carried out his calculations without the aid of a digital computer. D.H. Lemher extended and simplified Meissel's method in the context of modern computers, and calculated π(1010).

Miller and his co-authors present new algorithms that refine the Meissel-Lehmer method, including new sieving techniques and optimizations for parallel computing. Those interested in the technique are encouraged to read the paper. The “Extended Meiseel-Lehmer” technique is used to compute π(1016) as 279,238,341,033,925.

They also include an interesting chart comparing large values of π(x) and Li (x), the offset logarithmic integral that we presented in our article. Recall that Li(x) is an upper bound on the value of π(x). And for 1016, the difference between Li(x) and π(x) is 3,214,632. Only off by three million, which isn't too bad…

This post was included in Carnival of Mathematics #33 at Walking Randomly.