An item in the Sydney Morning Herald's Column 8
mentioned the following interesting mathematical tidbit - 2013 is the
start of a uncommon triplet of years which are all the products of three
distinct primes - 2013 = 3 x 11 x 61, 2014 = 2 x 19 x 53, and 2015 = 5
x 13 x 31.
When did this last happen? In 1885 (5 x 13 x
29), 1886 (2 x 23 x 41), 1887 (3 x 17 x 37), and before that, only in
the years 1309 (7 x 11 x 17), 1310 (2 x 5 x 131), 1311 (3 x 19 x 23). It
won't happen again until 2665 (5 x 13 x 41), 2666 (2 x 31 x 43), 2667
(3 x 7 x 127).
After that, the next such triplets are
3729-3731 and 5133-5135, but then it happens 5 times in the 7th
millenium (6061-6063, 6213-6215, 6477-6479, 6853-6855 and 6985-6987).
So if you want to stimulate a discussion about factors and/or prime numbers, 2013 is a great year.
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A discussion of Mathematics and computer programming and why logic is disappearing from public life.
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