x = (5 +/- sqrt(25-8)) / 4
= 5/4 +/- sqrt(17)/4
a = (5 + sqrt(17))/4
b = (5 - sqrt(17))/4
5 point 120
10 A=(5+sqrt(17))/4
20 B=(5-sqrt(17))/4
30 print (4*fnS(2017)+fnS(2015))/fnS(2016)
100 end
200 fnS(X)
210 S=A^(2*X)+B^(2*X)
220 return(S)
results in 21.0.
(Point 120 calls for 577 decimal positions after the decimal point.)
In fact, (4*S(k+1)+S(k-1))/S(k) = 21 for any k, even zero or negative.
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Posted by Charlie
on 2016-10-21 14:46:29 |
computer solution
