A021147 - OEIS

%I #25 Jul 08 2025 08:04:48

%S 0,0,6,9,9,3,0,0,6,9,9,3,0,0,6,9,9,3,0,0,6,9,9,3,0,0,6,9,9,3,0,0,6,9,

%T 9,3,0,0,6,9,9,3,0,0,6,9,9,3,0,0,6,9,9,3,0,0,6,9,9,3,0,0,6,9,9,3,0,0,

%U 6,9,9,3,0,0,6,9,9,3,0,0,6,9,9,3,0,0,6,9,9,3,0,0,6,9,9,3,0,0,6

%N Decimal expansion of 1/143.

%H Vincenzo Librandi, <a href="/A021147/b021147.txt">Table of n, a(n) for n = 0..1000</a>

%H <a href="/index/Rec#order_04">Index entries for linear recurrences with constant coefficients</a>, signature (1, 0, -1, 1).

%F From _Chai Wah Wu_, Jun 21 2016: (Start)

%F a(n) = a(n-1) - a(n-3) + a(n-4) for n > 3.

%F G.f.: 3*x^2*(2 + x)/(1 - x + x^3 - x^4). (End)

%t PadLeft[First@ #, Abs@ Last@ # + Length@ First@ #] &@ RealDigits[N[1/143, 120]] (* _Michael De Vlieger_, Jun 21 2016 *)

%o (Magma) I:=[0,0,6,9]; [n le 4 select I[n] else Self(n-1)- Self(n-3)+Self(n-4): n in [1..100]]; // _Vincenzo Librandi_, Jun 21 2016

%K nonn,cons,easy

%O 0,3

%A _N. J. A. Sloane_