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%I #22 Apr 07 2024 17:12:06
%S 1,-1,3,-4,7,-9,13,-16,21,-25,31,-36,43,-49,57,-64,73,-81,91,-100,111,
%T -121,133,-144,157,-169,183,-196,211,-225,241,-256,273,-289,307,-324,
%U 343,-361,381,-400,421,-441,463,-484,507,-529,553,-576,601,-625,651
%N a(n) = 3/8 + (3/8)*(-1)^n + ((n+1)/4)*(-1)^(n+1) + ((n+2)*(n+1)/4)*(-1)^(n+2).
%H <a href="/index/Rec#order_04">Index entries for linear recurrences with constant coefficients</a>, signature (-2,0,2,1)
%F O.g.f.: (1+z+z^2)/((1-z)*(1+z)^3).
%F a(n+4) = -2*a(n+3) + 2*a(n+1) + a(n).
%t LinearRecurrence[{-2,0,2,1},{1,-1,3,-4},60] (* _Harvey P. Dale_, Sep 23 2019 *)
%K sign,easy
%O 0,3
%A _Richard Choulet_, Nov 20 2008
%E More terms from 13; extended by _Richard Choulet_, Nov 26 2008
%E Definition corrected by _Paolo P. Lava_, Dec 02 2008