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%I #22 Sep 08 2022 08:45:51
%S 0,0,-1,3,0,8,3,15,8,24,15,35,24,48,35,63,48,80,63,99,80,120,99,143,
%T 120,168,143,195,168,224,195,255,224,288,255,323,288,360,323,399,360,
%U 440,399,483,440,528,483,575,528,624,575
%N a(n) = (2*n^2 - 2*n - 3)/8 + 3*(-1)^n*(1-2*n)/8.
%C First differences are (-1)^n*A022998(n).
%H Vincenzo Librandi, <a href="/A174474/b174474.txt">Table of n, a(n) for n = 0..1000</a>
%H <a href="/index/Rec#order_05">Index entries for linear recurrences with constant coefficients</a>, signature (1,2,-2,-1,1).
%F Bisections: a(2n) = A067998(n). a(2n+1) = A005563(n).
%F a(2n) + a(2n+1) = A001105(n).
%F a(n) = a(n-1) + 2*a(n-2) - 2*a(n-3) - a(n-4) + a(n-5).
%F G.f.: x^2*(1 - 4*x + x^2) / ( (1+x)^2*(x-1)^3 ).
%t LinearRecurrence[{1,2,-2,-1,1},{0,0,-1,3,0},60] (* _Harvey P. Dale_, Jun 01 2015 *)
%o (Magma) [(2*n^2-2*n-3)/8+3*(-1)^n*(1-2*n)/8: n in [0..60]]; // _Vincenzo Librandi_, Aug 04 2011
%K sign,easy
%O 0,4
%A _Paul Curtz_, Nov 28 2010