This site is supported by donations to The OEIS Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A006977 Cellular automaton with Rule 230: 000, 001, 010, 011, ..., 111 -> 0,1,1,0,0,1,1,1. (Formerly M2497) 5
 1, 3, 5, 15, 23, 59, 93, 239, 375, 955, 1501, 3823, 6007, 15291, 24029, 61167, 96119, 244667, 384477, 978671, 1537911, 3914683, 6151645, 15658735, 24606583, 62634939, 98426333, 250539759, 393705335, 1002159035, 1574821341, 4008636143, 6299285367 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,2 COMMENTS More precisely, this is the orbit of the initial value 1 under this Rule 230, cf. A292682. The substitution 100 -> 0 ensures that the initial 1 never extends to the right. - M. F. Hasler, Oct 09 2017 REFERENCES Marc LeBrun, personal communication. N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence). LINKS M. F. Hasler, Table of n, a(n) for n = 0..500 (First 200 terms from Sean A. Irvine.) A. J. Macfarlane, Generating functions for integer sequences defined by the evolution of cellular automata..., Fig 15. Eric Weisstein's World of Mathematics, Cellular Automaton. FORMULA Numbers suggest a rational g.f. with denominator (1-x^4)(1-4x^2). - Ralf Stephan, Jun 09 2005 G.f. seems to be (1 + 3*x + x^2 + 3*x^3 + 2*x^4 - 4*x^5)/((1 - x^4)*(1 - 4*x^2)). - Vincenzo Librandi, Sep 11 2017 EXAMPLE n  |    a(n) [binary] | a(n) [decimal]    0  |      ...01(0...) |   1    1  |     ...011(0...) |   3   (From ...010.., using 001 -> 1, 010 -> 1, 100 -> 0)    2  |    ...0101(0...) |   5   (001 -> 1, 011 -> 0, 110 -> 1, 100 -> 0)    3  |   ...01111(0...) |  15   (001 -> 1, 010 -> 1, 101 -> 1, 110 -> 1, 100 -> 0)    4  |  ...010111(0...) |  23   (001 -> 1, 011 -> 0, 111 -> 1, 110 -> 1)    5  | ...0111011(0...) |  59   (patterns of both of the above combined)    6  |...01011101(0...) |  93   (as above) MATHEMATICA FromDigits[#, 2] & /@ CellularAutomaton[230, {{1}, 0}, 32] (* Michael De Vlieger, Oct 09 2017 *) PROG (PARI) vector(90, i, a=if(i>1, A292682(a), 1)) CROSSREFS Cf. A292682; A292680, A292681, A266178, A266179, A266180; ... Sequence in context: A113732 A283908 A284409 * A284481 A290662 A003549 Adjacent sequences:  A006974 A006975 A006976 * A006978 A006979 A006980 KEYWORD nonn,easy AUTHOR EXTENSIONS Edited by M. F. Hasler, Oct 09 2017 STATUS approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified October 22 19:53 EDT 2019. Contains 328319 sequences. (Running on oeis4.)