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A127547
a(n) = 13*n + 4.
6
4, 17, 30, 43, 56, 69, 82, 95, 108, 121, 134, 147, 160, 173, 186, 199, 212, 225, 238, 251, 264, 277, 290, 303, 316, 329, 342, 355, 368, 381, 394, 407, 420, 433, 446, 459, 472, 485, 498, 511, 524, 537, 550, 563, 576, 589, 602, 615, 628, 641, 654, 667, 680, 693, 706, 719
OFFSET
0,1
COMMENTS
Superhighway created by 'LQTL Ant' L90R90L45R45 from iteration 4 where the Ant moves in a 'Moore neighborhood' (nine cells), the L indicates a left turn, the R a right turn, and the numerical value is the size of the turn (in degrees) at each iteration.
Ant Farm algorithm available from Robert H Barbour.
REFERENCES
P. Sakar, "A Brief History of Cellular Automata," ACM Computing Surveys, vol. 32, pp. 80-107, 2000.
LINKS
C. Langton, Studying Artificial Life with Cellular Automata, Physica D: Nonlinear Phenomena, vol. 22, pp. 120-149, 1986.
James Propp, Further Ant-ics, Mathematical Intelligencer, 16 pp. 37-42, 1994.
FORMULA
From Elmo R. Oliveira, Mar 21 2024: (Start)
G.f.: (4+9*x)/(1-x)^2.
E.g.f.: (4 + 13*x)*exp(x).
a(n) = 2*a(n-1) - a(n-2) for n >= 2. (End)
MATHEMATICA
Range[4, 1000, 13] (* Vladimir Joseph Stephan Orlovsky, May 31 2011 *)
PROG
(Magma) [13*n+4: n in [0..60]]; // G. C. Greubel, May 31 2024
(SageMath) [13*n+4 for n in range(61)] # G. C. Greubel, May 31 2024
CROSSREFS
A subsequence of A092464.
Sequences of the form 13*n+q: A008595 (q=0), A190991 (q=1), A153080 (q=2), this sequence (q=4), A154609 (q=5), A186113 (q=6), A269044 (q=7), A269100 (q=11).
Sequence in context: A272330 A163736 A249582 * A302410 A303177 A212756
KEYWORD
easy,nonn
AUTHOR
Robert H Barbour, Apr 01 2007
EXTENSIONS
Edited by N. J. A. Sloane, May 10 2007
STATUS
approved