login

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).

A041337
Denominators of continued fraction convergents to sqrt(182).
2
1, 2, 53, 108, 2861, 5830, 154441, 314712, 8336953, 16988618, 450041021, 917070660, 24293878181, 49504827022, 1311419380753, 2672343588528, 70792352682481, 144257048953490, 3821475625473221, 7787208299899932, 206288891422871453, 420364991145642838
OFFSET
0,2
FORMULA
G.f.: -(x^2-2*x-1) / (x^4-54*x^2+1). - Colin Barker, Nov 15 2013
a(n) = 54*a(n-2) - a(n-4). - Vincenzo Librandi, Dec 15 2013
MATHEMATICA
Denominator[Convergents[Sqrt[182], 30]] (* Harvey P. Dale, Jun 21 2013 *)
CoefficientList[Series[(1 + 2 x - x^2)/(x^4 - 54 x^2 + 1), {x, 0, 30}], x] (* Vincenzo Librandi, Dec 15 2013 *)
PROG
(Magma) I:=[1, 2, 53, 108]; [n le 4 select I[n] else 54*Self(n-2)-Self(n-4): n in [1..40]]; // Vincenzo Librandi, Dec 15 2013
CROSSREFS
Sequence in context: A062853 A059703 A212889 * A139844 A249657 A249658
KEYWORD
nonn,frac,easy
AUTHOR
EXTENSIONS
More terms from Colin Barker, Nov 15 2013
STATUS
approved