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%I #24 May 13 2013 01:54:20
%S 0,1,1,1,2,2,2,3,3,3,4,4,4,4,5,5,5,6,6,6,7,7,7,7,8,8,8,9,9,9,10,10,10,
%T 10,11,11,11,12,12,12,13,13,13,13,14,14,14,15,15,15,16,16,16,16,17,17,
%U 17,18,18,18,19,19,19,19,20,20,20,21,21,21,22,22,22
%N Let r be the largest real zero of x^n - x^(n-1) - x^(n-2) - ... - 1 = 0. Then a(n) is the value of k which satisfies the equation 0.5/10^k < 2 - r < 5/10^k.
%C Same as A034887 except for the offset and a(1). - _T. D. Noe_, Feb 11 2013
%H Charles R Greathouse IV, <a href="/A192543/b192543.txt">Table of n, a(n) for n = 1..10000</a>
%e For n = 5, the root is approximately r = 1.96594823. The value of k that satisfies 0.5/10^k < 2-r < 5/10^k is 2 as 0.005 < 0.03405177 < 0.05. So a(5) = 2.
%o (PARI) a(n)=if(n>1, -log(4-2*solve(x=1.5,2,x^n-(1-x^n)/(1-x)))\log(10)+1, 0) \\ _Charles R Greathouse IV_, Jan 15 2013
%K base,nonn
%O 1,5
%A _Ruskin Harding_, Dec 31 2012
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