A223673 - OEIS

%I #4 Mar 25 2013 09:40:47

%S 64,4096,61996,321163,1023339,2715255,6789502,16634224,40086061,

%T 94218637,214377471,470774847,998649425,2051656863,4092563126,

%U 7942987666,15025087905,27743027247,50072239147,88451496245,153108327757

%N Number of 6Xn 0..1 arrays with rows, diagonals and antidiagonals unimodal

%C Row 6 of A223669

%H R. H. Hardin, <a href="/A223673/b223673.txt">Table of n, a(n) for n = 1..129</a>

%F Empirical: a(n) = (271/5443200)*n^12 - (5527/1995840)*n^11 + (284203/2721600)*n^10 - (97799/51840)*n^9 - (4335667/259200)*n^8 + (68712079/30240)*n^7 - (50002254419/680400)*n^6 + (495395854627/362880)*n^5 - (42767475646507/2721600)*n^4 + (1367715597167/12960)*n^3 - (3261545344751/10800)*n^2 - (3687840940699/6930)*n + 4224261488 for n>20

%e Some solutions for n=4

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

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

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

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

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

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

%K nonn

%O 1,1

%A _R. H. Hardin_ Mar 25 2013