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”).

A041099
Denominators of continued fraction convergents to sqrt(57).
2
1, 1, 2, 9, 11, 20, 291, 311, 602, 2719, 3321, 6040, 87881, 93921, 181802, 821129, 1002931, 1824060, 26539771, 28363831, 54903602, 247978239, 302881841, 550860080, 8014922961, 8565783041, 16580706002
OFFSET
0,3
LINKS
FORMULA
From Colin Barker, Jul 18 2012: (Start)
a(n) = 302*a(n-6)-a(n-12).
G.f.: -(x^4-x^3+2*x^2+x+1)*(x^6-10*x^3-1)/(x^12-302*x^6+1). (End)
MATHEMATICA
Denominator[Convergents[Sqrt[57], 30]] (* Vincenzo Librandi, Oct 24 2013 *)
CROSSREFS
Sequence in context: A049343 A131140 A022114 * A041581 A042463 A081613
KEYWORD
nonn,cofr,frac,easy
AUTHOR
STATUS
approved