%I #21 Feb 01 2022 00:43:54
%S 2734,4556,6379,8202,10024,11846,13669,15492,17314,19136,20959,22782,
%T 24604
%N First differences of A145646.
%C Essentially (rounding effects ignored) 2*n+1 divided by the scaled constant A081821.
%F Conjectures from _Colin Barker_, May 08 2019: (Start)
%F G.f.: x*(2734 - 912*x + 2735*x^2 - 912*x^3) / ((1 - x)^2*(1 + x^2)).
%F a(n) = (3646 + (-i)^n + i^n + 7290*n) / 4 where i = sqrt(-1).
%F a(n) = 2*a(n-1) - 2*a(n-2) + 2*a(n-3) - a(n-4) for n>4.
%F (End)
%Y Cf. A081821, A145646.
%K nonn,easy,less
%O 1,1
%A _Paul Curtz_, Oct 15 2008
%E Edited by _N. J. A. Sloane_, Oct 15 2008 and _R. J. Mathar_, Oct 17 2008
%E Deleted keyword more: we do not want more terms of this ill-defined sequence. - _R. J. Mathar_, May 12 2019