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A116971
a(n) = (35*2^((2*(3*n+2) + 2)/3) - 2*(3*n+2) - 46)/9.
1
10, 56, 242, 988, 3974, 15920, 63706, 254852, 1019438, 4077784, 16311170, 65244716, 260978902, 1043915648, 4175662634, 16702650580, 66810602366, 267242409512, 1068969638098, 4275878552444, 17103514209830, 68414056839376
OFFSET
0,1
COMMENTS
Number of moves to solve Type 2 Zig-Zag puzzle.
REFERENCES
Richard I. Hess, Compendium of Over 7000 Wire Puzzles, privately printed, 1991.
Richard I. Hess, Analysis of Ring Puzzles, booklet distributed at 13th International Puzzle Party, Amsterdam, Aug 20 1993.
FORMULA
a(n) = 6*a(n-1)-9*a(n-2)+4*a(n-3). G.f.: 2*(5-2*x-2*x^2)/((1-x)^2*(1-4*x)). [Colin Barker, Sep 09 2012]
MATHEMATICA
Table[(35*2^((2*(3*n + 2) + 2)/3) - 2*(3*n + 2) - 46)/9, {n, 0, 30}] (* Stefan Steinerberger, Apr 02 2006 *)
LinearRecurrence[{6, -9, 4}, {10, 56, 242}, 30] (* Harvey P. Dale, Sep 08 2021 *)
PROG
(Magma) [Round((35*2^((2*(3*n + 2) + 2)/3 ) - 2*(3*n + 2) - 46)/9): n in [0..25]] // Vincenzo Librandi, Sep 09 2012
CROSSREFS
Sequence in context: A055911 A087076 A014483 * A200054 A034195 A351458
KEYWORD
nonn,easy
AUTHOR
N. J. A. Sloane, Apr 01 2006
STATUS
approved