A042238 - OEIS

%I #14 Mar 18 2017 16:15:30

%S 25,51,76,127,1600,16127,195124,211251,406375,1024001,51606425,

%T 104236851,155843276,260080127,3276804800,33028128127,399614342324,

%U 432642470451,832256812775,2097156096001,105690061612825,213477279321651,319167340934476,532644620256127

%N Numerators of continued fraction convergents to sqrt(645).

%H Vincenzo Librandi, <a href="/A042238/b042238.txt">Table of n, a(n) for n = 0..200</a>

%H <a href="/index/Rec#order_20">Index entries for linear recurrences with constant coefficients</a>, signature (0, 0, 0, 0, 0, 0, 0, 0, 0, 2048002, 0, 0, 0, 0, 0, 0, 0, 0, 0, -1).

%F G.f.: -(x^19 -25*x^18 +51*x^17 -76*x^16 +127*x^15 -1600*x^14 +16127*x^13 -195124*x^12 +211251*x^11 -406375*x^10 -1024001*x^9 -406375*x^8 -211251*x^7 -195124*x^6 -16127*x^5 -1600*x^4 -127*x^3 -76*x^2 -51*x -25) / (x^20 -2048002*x^10 +1). - _Colin Barker_, Dec 05 2013

%t Numerator[Convergents[Sqrt[645], 30]] (* _Vincenzo Librandi_, Nov 19 2013 *)

%Y Cf. A042239, A040619.

%K nonn,cofr,frac,easy

%O 0,1

%A _N. J. A. Sloane_.

%E More terms from _Colin Barker_, Dec 05 2013