I'm writing this from the NorCal Kakistan where we are once again without power for an indefinite time and where the CEO of the perpetrator has assured us tha this will be the new normal for the next decade. It ism't like I've never been to "third world countries", but they have never previously come to me. PG&E to serve its own needs and purposes has shut down power to large swaths of the state. They claim that this is all for our safety and our own good, but that is really all bullshit. This was not hithero normal; it only became normal once PG&E started being held responsible for the damages and harm resulting from events triggered by its most interesting repair and mintenance regime, which itself didn't use to be all that normal either.

Not far from here one can drive down a road lined with trees and power poles where the power lined un right through the crowns and branches of trees. Naturally, any remotely serious wind presents the spectre of tree to wire interaction tht could cause tree fire or a down line triggering a grass and brush fire. Because it would cost money to periodically trim the trees, they simply shut down the ocal sub-grid whenever moderately high winds are in the offing. Once he wind stops blowing, a few scarce crews will fly over the lines in helicopters and if the entire sub-grid displays no faults, they will power it back up. Naturally, if there are problems, then re-powering the sub-grid will await the ministrations of one of the few scarce repair and maintenance crews to said defects. The theory is that this will prevent power line caused fires without impairing the ability to pay healthy executive salaries and dividends due to maintenance and grid hardening costs. They appear, however, to have started a prety good fire, the Kincaid fire, all the same.

I'm doing this on a tablet in failing light and lack a lot of the tools I would normally use. The battery isn't all that happy either. Under good coditions, this thing can serve as it's own hotspot. You'll know how the conditions are if you see it posted. (My carrier's coverge is petty spotty)

Arithmetic is usually boring, and performed by rote, thugh there are hacks and cheats that bring it close to math. One classic involves application of the distributive law; a(b+c) = ab+ac, or, a(b-c) = ab-ac. This allows one to speed up computations such as 8x28 by reformulating them as 8(30-2) = 240-16 = 224. More trivially, the oft ignored associative law a(bc) = (ab)c is often instinctively used when one opts to first multiply the easiest pair of a triad to deal with, for example 12 times 14 times 5 would be routinely carried out as 12 times 14 = 168, times 5 = 840, but is arguably more readily performed as 14 times 5 = 70, times 12 = 840. None of these are particularly earth shaking but there is a much better method for multiplying two multi-digit numbers that the one most commonly in use.

Consider 123 times 456. In classic format, one mutiplies 6 times 3, which is 18, puts down the 8 and carries one, then six times two, plus the carried 1, is 13, with the 3 brought down and the one carried giving 6 times one, plus the carried 1 is 7, for the first row of the solution. One finds oneself carrying digits and keeping track of them both within the computation of any row of the solution as well as when totaling up the resultant columns to arrive at the complete solution. That generates unnecessary work. A better algorithm has been out there for quite a while but is pretty much not taught or explained to people. For the first row of the solution to the problem above one simply writes the answer to each pair-wise multiplication, from right to left, 18, 12, and 6. The next row, offset one column to the left is similarly simply 15, 10, and 5, again from right to left, and the last row similarly offset and from right to left is 12, 8, and 4. The carrying is reserved for adding the columns; 18 is 8 with one carried, 12 + 15 and that 1` is 28, which is 8 with 2 carried, 2 + 6 + 10 + 12 is 30, or 0 with 3 carried, 3 + 5 + 8 is 16, or 6 with one carried, and 4 = 1 is 5. The product is then 56088. once you get used to it, it is smoother and quicker.

Ok; the Schönhage–Strassen algorithm, got it? Fine, there's a possibly even slicker form. Add the columns above with no carries getting an intermediate line of totals, from left to right this time, 4,13,28,27,18. Now, starting on the right, keep the 8, then 1+7=8 again, 2+8=10 so keep the zero,1+2+3=6,1+4=5, and, voila' 56088. If you recall that you're working with ever increasing powers of ten it makes perfect sense in both forms.

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Its an open thread so have at it. The floor is yours
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My presence or absence depends upon the whim of PG&E, follower by the whim of my phone+isp providers should I try to use by tablet.