A010724 Period 2: repeat (6,8).

6, 8, 6, 8, 6, 8, 6, 8, 6, 8, 6, 8, 6, 8, 6, 8, 6, 8, 6, 8, 6, 8, 6, 8, 6, 8, 6, 8, 6, 8, 6, 8, 6, 8, 6, 8, 6, 8, 6, 8, 6, 8, 6, 8, 6, 8, 6, 8, 6, 8, 6, 8, 6, 8, 6, 8, 6, 8, 6, 8, 6, 8, 6, 8, 6, 8, 6, 8, 6, 8, 6, 8, 6, 8, 6, 8, 6, 8, 6, 8, 6

Offset: 0

Author

N. J. A. Sloane

Keywords

• nonn
• easy

Comments

Decimal expansion of 68/99. - David A. Corneth, Oct 18 2016

Links

• Index entries for linear recurrences with constant coefficients, signature (0,1).

Crossrefs

Cf. A176401.

Programs

Mathematica

NestList[10 - EulerPhi@ # &, 6, 120] (* or *)
CoefficientList[Series[(-6 - 8 x)/((x - 1) (1 + x)), {x, 0, 120}], x] (* Michael De Vlieger, Oct 21 2016 *)

PARI

a(n)=6+n%2*2 \\ Charles R Greathouse IV, Dec 08 2015

Formula

a(n) = (-1)^(n+1)+7. - Paolo P. Lava, Oct 27 2006

G.f.: ( -6-8*x ) / ((x-1)*(1+x)). - R. J. Mathar, Nov 21 2011

a(0)=6, a(n) = 10 - eulerphi(a(n-1)) for n>0. - Alexander R. Povolotsky, Oct 16 2016