%I #16 Jul 28 2024 16:50:04
%S 40,39,38,37,36,35,34,33,32,31,30,29,28,27,26,25,24,23,22,21,20,19,18,
%T 17,16,15,14,13,12,11,10,9,8,7,6,5,4,3,2,1,0,-1,-2,-3,-4,-5,-6,-7,-8,
%U -9,-10,-11,-12,-13,-14,-15,-16,-17,-18,-19,-20
%N a(n) = 40-n.
%H Tanya Khovanova, <a href="http://www.tanyakhovanova.com/RecursiveSequences/RecursiveSequences.html">Recursive Sequences</a>.
%H <a href="/index/Rec#order_02">Index entries for linear recurrences with constant coefficients</a>, signature (2,-1).
%t 40 - Range[0, 100] (* _Paolo Xausa_, Jul 28 2024 *)
%o (PARI) a(n)=40-n \\ _Charles R Greathouse IV_, Jul 10 2016
%Y Cf. A022958 - A022995.
%K sign,easy
%O 0,1
%A _N. J. A. Sloane_