%I#8 2015年2月19日14:43:48
%S 1,3,9,23,5714135187521815435135433374784093209549522169,
%电话:1301177324236380795452013317150169233125015177311521495,
%电话:776270883193436566548201866231201127558329930530167745829724651851027385
%N长度为1、2或3且和为零的子序列中,每个x(i)包含-1..1个整数x(1..N)的数组的数目
%A193702的C列1
%H R.H.Hardin,n表,n=1..200的a(n)</a>
%F经验:a(n)=2*a(n-1)+a(n-2)+a。
%F经验:G.F.:x*(-1-x-2*x^2-2*x^3-x^4)/(-1+2*x+x^2+x^4+x^5)。-_R.J.Mathar,2015年2月19日
%e n=6的一些解
%e、-1....0....1....0....0....0....0....0....1...-1....1....1....0....1...-1....0
%e。。1...-1...-1....0....0....0...-1....1...-1....1...-1...-1....0...-1....1...-1
%e。。0....1....1....0....1....0....0...-1....0....1....1....1....1....1...-1....1
%e。。0....0....1....1....0...-1....1....0....0...-1...-1....0...-1...-1....0...-1
%e。。1...-1...-1...-1...-1....1....1....0....1....0....1....0....0....0....1....1
%e、-1....0....0....1....1....0...-1....0...-1....0...-1....0....0....1...-1....0
%K nonn公司
%O 1,2号机组
%A R.H.Hardin(2011年8月2日)