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A042105
Denominators of continued fraction convergents to sqrt(577).
3
1, 48, 2305, 110688, 5315329, 255246480, 12257146369, 588598272192, 28264974211585, 1357307360428272, 65179018274768641, 3129950184549323040, 150302787876642274561, 7217663768263378501968, 346598163664518810369025, 16643929519665166276215168
OFFSET
0,2
COMMENTS
From Michael A. Allen, Dec 02 2023: (Start)
Also called the 48-metallonacci sequence; the g.f. 1/(1-k*x-x^2) gives the k-metallonacci sequence.
a(n) is the number of tilings of an n-board (a board with dimensions n X 1) using unit squares and dominoes (with dimensions 2 X 1) if there are 48 kinds of squares available. (End)
LINKS
FORMULA
a(n) = F(n, 48), the n-th Fibonacci polynomial evaluated at x=48. - T. D. Noe, Jan 19 2006
From Philippe Deléham, Nov 23 2008: (Start)
a(n) = 48*a(n-1) + a(n-2), n>1; a(0)=1, a(1)=48.
G.f.: 1/(1 - 48*x - x^2). (End)
MATHEMATICA
a=0; lst={}; s=0; Do[a=s-(a-1); AppendTo[lst, a]; s+=a*48, {n, 3*4!}]; lst (* Vladimir Joseph Stephan Orlovsky, Nov 03 2009 *)
Denominator[Convergents[Sqrt[577], 30]] (* Vincenzo Librandi, Jan 14 2014 *)
LinearRecurrence[{48, 1}, {1, 48}, 20] (* Harvey P. Dale, Aug 21 2019 *)
CROSSREFS
Row n=48 of A073133, A172236 and A352361 and column k=48 of A157103.
Sequence in context: A158783 A227139 A009992 * A206046 A079240 A360904
KEYWORD
nonn,frac,easy,changed
EXTENSIONS
Additional term from Colin Barker, Dec 01 2013
STATUS
approved

  NODES
COMMUNITY 1
INTERN 1