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”).

A042414
Numerators of continued fraction convergents to sqrt(735).
3
27, 244, 13203, 119071, 6443037, 58106404, 3144188853, 28355806081, 1534357717227, 13837575261124, 748763421817923, 6752708371622431, 365395015489429197, 3295307847776485204, 178312018795419630213
OFFSET
0,1
FORMULA
G.f.: (27 +244*x +27*x^2 -x^3)/(1 -488*x^2 +x^4). - Vincenzo Librandi, Nov 23 2013
a(n) = 488*a(n-2) - a(n-4). - Vincenzo Librandi, Nov 23 2013
MATHEMATICA
Numerator[Convergents[Sqrt[735], 30]] (* or *) CoefficientList[Series[(27 + 244 x + 27 x^2 - x^3)/(1 - 488 x^2 + x^4), {x, 0, 30}], x] (* Vincenzo Librandi, Nov 23 2013 *)
PROG
(Magma) I:=[27, 244, 13203, 119071]; [n le 4 select I[n] else 488*Self(n-2)-Self(n-4): n in [1..30]]; // Vincenzo Librandi, Nov 23 2013
CROSSREFS
Cf. A042415.
Sequence in context: A345054 A074117 A030509 * A099226 A016107 A101379
KEYWORD
nonn,cofr,frac,easy
AUTHOR
STATUS
approved