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Meta
Category Archives: sciences
some thoughts about packing
My bundle of 19 fullerenes is arranged in a face-centred cubic lattice, each ball occupying one of the 24 even-numbered cells of a 4×4×3 array (and parts of the adjacent cells). The spacing of the grid planes is determined by … Continue reading
Posted in mathematics
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small irregular fullerenes
Shapeways has thirteen models of (the most symmetrical and famous form of) C60, but none of the thousands of smaller fullerenes. So I designed models of the 35 smallest, i.e. up to C36; this includes the smallest with no symmetries, … Continue reading
amazing restraint
Roderick Long defines right-conflationism as defending existing economic structures as if they were outcomes of a genuinely free market (what Kevin Carson calls vulgar libertarianism), and left-conflationism as using those outcomes to attack the concept of free markets. I hope … Continue reading
Posted in economics, politics
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do you speak my calendar?
In MacBSD, the command cal 9 1752 shows the shortening of that month in the British Empire. If I reinstall MacOS and choose Italian as its default language, will the shift show up instead in October 1582?
Posted in calendars, history, neep-neep
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as many as it takes
allRGB: images in which each of 16 million colors occurs exactly once. (Found at MathPuzzle.) I see I’m not the only one to think of the Hilbert curve idea, but I’ll post two others. In unrelated news, I was surprised … Continue reading
Posted in Cascadia, eye-candy, mathematics
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it’s all connected
My old calculus book gives a formula for the curvature of a parametric arc in the plane — that is, an arc defined by two functions (x(t),y(t)) of one variable. For thirty years I didn’t think about the derivation of … Continue reading
Posted in curve-fitting
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High Throw
Read this first. To throw for maximum distance (on an infinite plane in a vacuum), you aim at 45° elevation; in other words, split kinetic energy evenly between vertical and lateral velocity. (I dimly remember having proven that, but am … Continue reading
Posted in sciences
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