login
A042735
Denominators of continued fraction convergents to sqrt(897).
2
1, 1, 19, 20, 1179, 1199, 22761, 23960, 1412441, 1436401, 27267659, 28704060, 1692103139, 1720807199, 32666632721, 34387439920, 2027138148081, 2061525588001, 39134598732099, 41196124320100, 2428509809297899, 2469705933617999, 46883216614421881
OFFSET
0,3
LINKS
FORMULA
G.f.: -(x^2-x-1)*(x^4+20*x^2+1) / (x^8-1198*x^4+1). - Colin Barker, Dec 22 2013
a(n) = 1198*a(n-4) - a(n-8) for n>7. - Vincenzo Librandi, Jan 27 2014
MATHEMATICA
Denominator[Convergents[Sqrt[897], 30]] (* Harvey P. Dale, May 29 2013 *)
PROG
(Magma) I:=[1, 1, 19, 20, 1179, 1199, 22761, 23960]; [n le 8 select I[n] else 1198*Self(n-4)-Self(n-8): n in [1..30]]; // Vincenzo Librandi, Jan 27 2014
CROSSREFS
Sequence in context: A041756 A041757 A041758 * A156758 A089837 A020347
KEYWORD
nonn,frac,easy
AUTHOR
EXTENSIONS
More terms from Colin Barker, Dec 22 2013
STATUS
approved