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%I #26 Jan 03 2024 08:48:26
%S -1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
%T 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
%U 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1
%N -1 followed by infinitely many 1's.
%C Up to the sign of a(0), the same as the "all ones" sequence A000012. - _M. F. Hasler_, May 30 2020
%H <a href="/index/Rec#order_01">Index entries for linear recurrences with constant coefficients</a>, signature (1).
%F G.f.: (2x-1)/(1-x). - _Philippe Deléham_, Mar 19 2009
%F a(n) = (-1)^A000007(n) = (-1)^[n=0], where [.] is the Iverson bracket. - _M. F. Hasler_, May 30 2020
%t PadRight[{-1},120,1] (* _Harvey P. Dale_, Apr 05 2023 *)
%o (PARI) a(n)=if(n,1,-1) \\ _Charles R Greathouse IV_, Jun 13 2013
%o (PARI) apply( {A158388(n)=1-!n*2}, [0..90]) \\ _M. F. Hasler_, May 30 2020
%Y Cf. A000012, A000007.
%K sign,mult,easy
%O 0,1
%A _Jaroslav Krizek_, Mar 17 2009