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The life of Diophantus.
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%I #11 Mar 24 2015 16:16:50

%S 0,14,21,33,38,80,84

%N The life of Diophantus.

%C From the riddle on the tombstone of Diophantus. See the reference and the links.

%D H.-W. Alten et al., 4000 Jahre Algebra, 2. Auflage, Springer, 2014, p. 63.

%H David Pleacher, <a href="http://www.pleacher.com/mp/mfacts/dioph.html">Diophantus' epitaph</a>.

%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/DiophantussRiddle.html">Diophantus's Riddle</a>.

%H Wikipedia, <a href="https://en.wikipedia.org/wiki/Diophantus">Diophantus</a>.

%F a(0): birth (all numbers a(n) in years), a(1): boyhood ended, a(2): beard started to grow, a(3): marriage, a(4): birth of son, a(5): death of son, a(6): death of Diophantus.

%e a(1) = age/6,

%e a(2) = age*(1/6 + 1/12) = age/4,

%e a(3) = age*(1/4 + 1/7) = age*11/28,

%e a(4) = age*11/28 + 5,

%e a(5) = age(11/28 + 1/2) + 5 = age*25/28 + 5,

%e a(6) = age*25/28 + 5 + 4 = age,

%e hence age*(1-25/28) = 9, age = 28*3 = 84.

%K nonn,fini,full

%O 0,2

%A _Wolfdieter Lang_, Jan 31 2015