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%I #5 Mar 30 2012 18:57:56
%S 5,9,4,7,3,0,0,2,9,2,2,8,2,2,7,8,3,1,5,0,1,1,1,5,0,8,4,2,6,0,7,9,7,7,
%T 1,1,8,3,6,3,3,1,5,8,8,4,1,4,9,3,4,4,9,9,6,7,6,2,9,0,9,5,0,6,2,1,8,1,
%U 7,2,9,3,0,6,1,3,8,8,2,5,5,1,1,9,0,3,2,7,0,3,5,0,4,5,0,4,6,6,2
%N Decimal expansion of the least x>0 that gives the absolute minimum of f(x)+f(2x)+f(3x), where f(x)=sin(x)-cos(x).
%C See A198745 for a guide to related sequences.
%e x=5.94730029228227831501115084260797711836331...
%e min=-4.05824487647797618374998236242336948409...
%t f[t_] := Sin[t] - Cos[t]
%t n = 3; s[t_] := Sum[f[k*t], {k, 1, n}]
%t x = N[Minimize[s[t], t], 110]; u = Part[x, 1]
%t v = t /. Part[x, 2]
%t RealDigits[u] (* A198747 *)
%t RealDigits[v] (* A198748 *)
%t Plot[s[t], {t, -2 Pi, 2 Pi}, PlotRange -> {-4.1, 3}]
%Y Cf. A198745.
%K nonn,cons
%O 1,1
%A _Clark Kimberling_, Oct 29 2011