Tip: where to get the periodic table of the chemical elements

My favorite official source to download printable copies of the periodic table of the chemical elements (also known in the post-USSR countries as the Mendeleev's table) is IUPAC (the International Union of Pure and Applied Chemistry):

• IUPAC Periodic Table of the Elements

(Currently, the table on the IUPAC site dates back to 2016-11-28).

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Last updated: 2017-02-11

HOWTO: the poor man's random number generator

Spoiler: the described binary random number generator (RNG) usually doesn't consume any electricity, but still definitely needs a minimal investment :-)