login

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).

Number of length n 0..4 arrays with new values introduced in order from both ends, and least squares fitting to a straight line with slope zero, with a single point taken as having zero slope
1

%I #4 Aug 04 2014 07:27:17

%S 1,1,2,2,5,5,15,17,78,102,568,918,6115,11063,84095,167139,1377562,

%T 2919818,25322454,55877190,500009859,1130615111,10314022021,

%U 23685168139,218801537756,507728746032,4731965243042,11064419359152,103808357373783

%N Number of length n 0..4 arrays with new values introduced in order from both ends, and least squares fitting to a straight line with slope zero, with a single point taken as having zero slope

%C Column 4 of A245851

%H R. H. Hardin, <a href="/A245847/b245847.txt">Table of n, a(n) for n = 1..123</a>

%e Some solutions for n=12

%e ..0....0....0....0....0....0....0....0....0....0....0....0....0....0....0....0

%e ..0....0....1....1....1....0....1....1....1....1....1....1....0....1....1....1

%e ..1....0....0....1....2....1....2....0....0....0....0....2....0....1....2....2

%e ..1....1....2....2....2....1....1....2....0....2....0....3....1....0....0....3

%e ..2....0....0....1....3....0....3....2....1....1....1....3....2....2....1....2

%e ..1....2....2....1....0....0....1....3....1....0....1....1....2....1....2....0

%e ..0....2....1....2....0....0....2....0....2....0....1....4....2....3....3....2

%e ..1....0....1....3....3....0....1....3....2....2....1....2....2....1....2....3

%e ..0....1....2....2....2....1....2....2....1....0....0....3....1....2....2....2

%e ..1....0....1....0....2....1....2....0....0....1....0....2....0....1....0....2

%e ..1....0....0....1....1....0....1....1....0....1....1....1....0....0....1....1

%e ..0....0....0....0....0....0....0....0....0....0....0....0....0....0....0....0

%K nonn

%O 1,3

%A _R. H. Hardin_, Aug 04 2014