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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
2, 4, 7, 11, 13, 22, 23, 332, 560, 565, 566, 568, 3249, 3258, 3265, 3275, 3303, 3308, 3311, 3315, 3578, 3580, 3581, 3585, 3587, 3589, 3596, 3622, 3623, 3628, 3631, 4649, 4650, 4652, 4659, 4661, 4685, 4700, 4701, 5963, 5966, 5969, 6035, 6039, 6066, 6069 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..46.

EXAMPLE

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

CROSSREFS

Sequence in context: A327572 A177754 A086795 * A138766 A192638 A211372

Adjacent sequences:  A064687 A064688 A064689 * A064691 A064692 A064693

KEYWORD

nonn

AUTHOR

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

STATUS

approved

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Last modified April 7 15:56 EDT 2020. Contains 333306 sequences. (Running on oeis4.)