A186528 Number of (n+1)X2 0..2 arrays with no 2X2 subblock determinant equal to any horizontal or vertical neighbor 2X2 subblock determinant

81, 554, 4020, 28522, 203346, 1448300, 10317234, 73494218, 523535260, 3729392026, 26566253962, 189244190416, 1348077312794, 9603002534510, 68406801866740, 487294523222534, 3471233063104946, 24727261243092472, 176144164759542978

Offset

1,1

Comments

Column 1 of A186536

Links

R. H. Hardin, Table of n, a(n) for n = 1..200

Formula

Empirical: a(n)=3*a(n-1)+17*a(n-2)+66*a(n-3)+129*a(n-4)+183*a(n-5)+162*a(n-6)-29*a(n-7)-150*a(n-8)-189*a(n-9)-109*a(n-10)-2*a(n-11)+8*a(n-12) for n>13

Example

Some solutions for 3X2
..2..2....2..2....2..0....0..0....1..1....2..0....2..2....1..1....0..2....2..2
..1..0....2..2....2..1....2..0....1..2....2..1....2..2....2..2....0..1....2..0
..2..2....2..0....0..2....1..2....2..2....1..0....0..1....1..2....1..1....1..0

Crossrefs

Sequence in context: A231973 A205894 A186536 * A253294 A253164 A185777

Adjacent sequences: A186525 A186526 A186527 * A186529 A186530 A186531

Keyword

nonn

Author

R. H. Hardin Feb 23 2011

Status

approved