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a(0) = -3; a(n) = n-a(n-1).
7

%I #10 Jan 09 2021 13:53:07

%S -3,4,-2,5,-1,6,0,7,1,8,2,9,3,10,4,11,5,12,6,13,7,14,8,15,9,16,10,17,

%T 11,18,12,19,13,20,14,21,15,22,16,23,17,24,18,25,19,26,20,27,21,28,22,

%U 29,23,30,24,31,25,32,26,33,27,34,28,35,29,36,30,37,31,38,32,39,33,40,34

%N a(0) = -3; a(n) = n-a(n-1).

%F a(n) = (2n+1-13*(-1)^n)/4. G.f.: -(3-7x+3x^2)/((1+x)(1-x)^2). - _R. J. Mathar_, Jan 08 2009

%t lst={};a=3;Do[a=n-a;AppendTo[lst,a],{n,0,6!}];lst

%t RecurrenceTable[{a[0]==-3,a[n]==n-a[n-1]},a,{n,80}] (* _Harvey P. Dale_, May 16 2016 *)

%Y Cf. A084964, A152832.

%K sign

%O 0,1

%A _Vladimir Joseph Stephan Orlovsky_, Dec 14 2008

%E Indices added to definition, offset corrected by _R. J. Mathar_, Jan 08 2009