login
A041215
Denominators of continued fraction convergents to sqrt(118).
2
1, 1, 7, 22, 51, 532, 1115, 3877, 24377, 28254, 589457, 617711, 4295723, 13504880, 31305483, 326559710, 684424903, 2379834419, 14963431417, 17343265836, 361828748137, 379172013973, 2636860831975, 8289754509898, 19216369851771, 200453453027608
OFFSET
0,3
LINKS
Index entries for linear recurrences with constant coefficients, signature (0,0,0,0,0,0,0,0,0,613834,0,0,0,0,0,0,0,0,0,-1).
FORMULA
G.f.: -(x^18 -x^17 +7*x^16 -22*x^15 +51*x^14 -532*x^13 +1115*x^12 -3877*x^11 +24377*x^10 -28254*x^9 -24377*x^8 -3877*x^7 -1115*x^6 -532*x^5 -51*x^4 -22*x^3 -7*x^2 -x -1) / (x^20 -613834*x^10 +1). - Colin Barker, Nov 14 2013
a(n) = 613834*a(n-10) - a(n-20). - Vincenzo Librandi, Dec 13 2013
MATHEMATICA
Denominator[Convergents[Sqrt[118], 30]] (* Vincenzo Librandi, Dec 13 2013 *)
PROG
(Magma) I:=[1, 1, 7, 22, 51, 532, 1115, 3877, 24377, 28254, 589457, 617711, 4295723, 13504880, 31305483, 326559710, 684424903, 2379834419, 14963431417, 17343265836]; [n le 20 select I[n] else 613834*Self(n-10)-Self(n-20): n in [1..40]]; // Vincenzo Librandi, Dec 13 2013
CROSSREFS
Sequence in context: A211635 A211634 A184629 * A060822 A011926 A101120
KEYWORD
nonn,frac,easy
AUTHOR
EXTENSIONS
More terms from Colin Barker, Nov 14 2013
STATUS
approved