%I #16 Jul 29 2024 09:15:48
%S 39,38,37,36,35,34,33,32,31,30,29,28,27,26,25,24,23,22,21,20,19,18,17,
%T 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,-9,
%U -10,-11,-12,-13,-14,-15,-16,-17,-18,-19,-20,-21
%N a(n) = 39 - n.
%C If we extend this sequence to negative n, then we have a permutation of the integers. - _Alonso del Arte_, Aug 02 2017
%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).
%F a(n) = -n + 39.
%t 39 - Range[0, 59] (* _Alonso del Arte_, Aug 02 2017 *)
%Y Cf. A022958 - A022996.
%K sign,easy
%O 0,1
%A _N. J. A. Sloane_