A004445 - OEIS

%I #17 Nov 22 2016 02:57:50

%S 4,5,6,7,0,1,2,3,12,13,14,15,8,9,10,11,20,21,22,23,16,17,18,19,28,29,

%T 30,31,24,25,26,27,36,37,38,39,32,33,34,35,44,45,46,47,40,41,42,43,52,

%U 53,54,55,48,49,50,51,60,61

%N Nimsum n + 4.

%C A self-inverse permutation of the natural numbers. - _Philippe Deléham_, Nov 22 2016

%D E. R. Berlekamp, J. H. Conway and R. K. Guy, Winning Ways, Academic Press, NY, 2 vols., 1982, see p. 60.

%D J. H. Conway, On Numbers and Games. Academic Press, NY, 1976, pp. 51-53.

%H <a href="/index/Ni#Nimsums">Index entries for sequences related to Nim-sums</a>

%H <a href="/index/Rec#order_06">Index entries for linear recurrences with constant coefficients</a>, signature (2,-1,0,-1,2,-1)

%F G.f.: [4-3x-4x^4+5x^5]/[(1-x)^2(1+x^4)]. - _Ralf Stephan_, Apr 24 2004

%F a(n) = n + 4(-1)^[n/4]. - Mitchell Harris, Jan 10 2005

%K nonn

%O 0,1

%A _N. J. A. Sloane_