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%I #6 May 10 2013 12:45:34
%S 2,26,264,2646,26464,264649,2646494,26464944,264649443,2646494434,
%T 26464944348,264649443484,2646494434842,26464944348425,
%U 264649443484250,2646494434842508,26464944348425087
%N Number of digits of the 10^n-th tribonacci number (A000073).
%C a(n)/10^n tends towards log[10](rho) = .26464944348425087191..., where rho is the real root of x^3-x^2-x-1 = 0. - _Vladeta Jovovic_, Sep 01 2004
%t rho=1/3*((19+3*Sqrt[33])^(1/3)+(19-3*Sqrt[33])^(1/3)+1); triboappr[n_]:=N[(rho-1)/(4rho-6)*rho^(n-3), 3000]; Table[MantissaExponent[triboappr[10^i]][[2]], {i, 1, 7}]
%Y Cf. A068070.
%K nonn,easy,base
%O 0,1
%A _Michael Taktikos_, Aug 09 2004
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