%I #23 Dec 23 2023 16:16:12
%S 2,-1,-3,-2,1,3,2,-1,-3,-2,1,3,2,-1,-3,-2,1,3,2,-1,-3,-2,1,3,2,-1,-3,
%T -2,1,3,2,-1,-3,-2,1,3,2,-1,-3,-2,1,3,2,-1,-3,-2,1,3,2,-1,-3,-2,1,3,2,
%U -1,-3,-2,1,3,2,-1,-3,-2,1,3,2,-1,-3,-2,1,3,2,-1,-3,-2
%N a(n) = a(n-1) - a(n-2), with a(0)=2, a(1)=-1.
%D Rosen, Discrete Mathematics and its Applications, McGraw-Hill, 2007, p. 456, Question 1b.
%H <a href="/index/Rec#order_02">Index entries for linear recurrences with constant coefficients</a>, signature (1,-1).
%F G.f.: ( 2-3*x ) / ( 1-x+x^2 ). - _R. J. Mathar_, Jan 08 2011
%p a[0] := 2: a[1] := -1: for n from 2 to 80 do a[n] := a[n-1]-a[n-2] end do: seq(a[n], n = 0 .. 75); # _Emeric Deutsch_, Apr 05 2010
%K sign,easy
%O 0,1
%A Zachary Berger (zsb1244(AT)rit.edu), Mar 28 2010
%E Typo in definition fixed by _Emeric Deutsch_, Apr 05 2010