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A126978
a(n) = 104*n + 9977.
5
9977, 10081, 10185, 10289, 10393, 10497, 10601, 10705, 10809, 10913, 11017, 11121, 11225, 11329, 11433, 11537, 11641, 11745, 11849, 11953, 12057, 12161, 12265, 12369, 12473, 12577, 12681, 12785, 12889, 12993, 13097, 13201, 13305, 13409, 13513, 13617, 13721, 13825
OFFSET
0,1
COMMENTS
Langton's Ant Superhighway, the start point (9977th iteration, J. Propp) and the period length for the Superhighway (104).
LINKS
C. Langton, Studying Artificial Life with Cellular Automata, Physica D: Nonlinear Phenomena, Vol. 22, 1986, pp. 120-149.
Ed Pegg Jr, 2D Turing Machines, 2004.
James Propp, Further Ant-ics, Mathematical Intelligencer, Vol. 16, 1994, pp. 37-42.
P. Sarkar, A Brief History of Cellular Automata, ACM Computing Surveys. Vol. 32, No. 1, Mar 01 2000, pp. 80-107.
S. Wolfram, 2D Turing Machines.
FORMULA
a(0)=9977, a(1)=10081, a(n) = 2*a(n-1) - a(n-2). - Harvey P. Dale, Dec 16 2011
G.f.: (9977 - 9873*x)/(1-x)^2. - Vincenzo Librandi, Sep 10 2015
E.g.f.: exp(x)*(9977 + 104*x). - Elmo R. Oliveira, Dec 08 2024
MATHEMATICA
104*Range[0, 40]+9977 (* or *) LinearRecurrence[{2, -1}, {9977, 10081}, 40] (* Harvey P. Dale, Dec 16 2011 *)
CoefficientList[Series[(9977 - 9873 x)/(1 - x)^2, {x, 0, 40}], x] (* Vincenzo Librandi, Sep 10 2015 *)
PROG
(Magma) [104*n + 9977: n in [0..40]]; // Vincenzo Librandi, Sep 10 2015
(PARI) a(n)=104*n+9977 \\ Charles R Greathouse IV, Oct 07 2015
CROSSREFS
KEYWORD
easy,nonn
AUTHOR
Robert H Barbour, Mar 20 2007, Jun 12 2007
STATUS
approved