cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A116969 If n mod 2 = 0 then 3*2^(n-1)+n-1 else 3*2^(n-1)+n.

Original entry on oeis.org

4, 7, 15, 27, 53, 101, 199, 391, 777, 1545, 3083, 6155, 12301, 24589, 49167, 98319, 196625, 393233, 786451, 1572883, 3145749, 6291477, 12582935, 25165847, 50331673, 100663321, 201326619, 402653211, 805306397, 1610612765, 3221225503, 6442450975, 12884901921
Offset: 1

Views

Author

N. J. A. Sloane, Apr 01 2006

Keywords

Comments

Number of moves to solve Easy Pagoda 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.

Programs

  • Maple
    f:=n-> if n mod 2 = 0 then 3*2^(n-1)+n-1 else 3*2^(n-1)+n; fi;
  • Mathematica
    f[n_]:=If[EvenQ[n],3*2^(n-1)+n-1,3*2^(n-1)+n]; f/@Range[40] (* Harvey P. Dale, Sep 21 2012 *)

Formula

a(n) = 3*a(n-1)-a(n-2)-3*a(n-3)+2*a(n-4). G.f.: -x*(x^3-2*x^2-5*x+4) / ((x-1)^2*(x+1)*(2*x-1)). - Colin Barker, Jul 18 2013

Extensions

More terms from Colin Barker, Jul 18 2013