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A168321 a(n) = n - a(n-1), with a(0) = 7. 1
0, 8, 1, 9, 2, 10, 3, 11, 4, 12, 5, 13, 6, 14, 7, 15, 8, 16, 9, 17, 10, 18, 11, 19, 12, 20, 13, 21, 14, 22, 15, 23, 16, 24, 17, 25, 18, 26, 19, 27, 20, 28, 21, 29, 22, 30, 23, 31, 24, 32, 25, 33, 26, 34, 27, 35, 28, 36, 29, 37, 30, 38, 31, 39, 32, 40, 33, 41, 34, 42, 35, 43, 36 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

G. C. Greubel, Table of n, a(n) for n = 1..1000

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

FORMULA

From R. J. Mathar, Nov 23 2009: (Start)

a(n) = a(n-1) + a(n-2) - a(n-3).

a(n) = (13 + 15*(-1)^n + 2*n)/4.

G.f.: x^2*(8 - 7*x)/((1+x)*(1-x)^2). (End)

E.g.f.: (1/4)*(15 - 28*exp(x) + (13 + 2*x)*exp(2*x))*exp(-x). - G. C. Greubel, Jul 17 2016

MATHEMATICA

a=7; Table[a=n-a, {n, a, 200}]

LinearRecurrence[{1, 1, -1}, {0, 8, 1}, 50] (* G. C. Greubel, Jul 17 2016 *)

PROG

(MAGMA) [(13+15*(-1)^n+2*n)/4: n in [1..80]]; // Vincenzo Librandi, Jul 18 2016

CROSSREFS

Sequence in context: A308043 A286253 A198674 * A242047 A176455 A225667

Adjacent sequences:  A168318 A168319 A168320 * A168322 A168323 A168324

KEYWORD

nonn

AUTHOR

Vladimir Joseph Stephan Orlovsky, Nov 22 2009

STATUS

approved

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Last modified June 20 09:12 EDT 2019. Contains 324234 sequences. (Running on oeis4.)