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 A064690 Define a sequence of fractions by x(m+1) = (x(m)^2+x(m)-1)/(x(m)+1) with x(1)=1; sequences gives values of n such that sgn(x(n))<>sgn(x(n-1)). 0

%I

%S 2,4,7,11,13,22,23,332,560,565,566,568,3249,3258,3265,3275,3303,3308,

%T 3311,3315,3578,3580,3581,3585,3587,3589,3596,3622,3623,3628,3631,

%U 4649,4650,4652,4659,4661,4685,4700,4701,5963,5966,5969,6035,6039,6066,6069

%N Define a sequence of fractions by x(m+1) = (x(m)^2+x(m)-1)/(x(m)+1) with x(1)=1; sequences gives values of n such that sgn(x(n))<>sgn(x(n-1)).

%e x(0)=1, x(1) = 1/2, x(2) = -1/6 so a(1) = 2 because sgn(x(1)) <> sgn(x(2))

%K nonn

%O 1,1

%A Jonathan Ayres (jonathan.ayres(AT)btinternet.com), Oct 16 2001

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Last modified May 30 15:21 EDT 2020. Contains 334726 sequences. (Running on oeis4.)