A185481 Number of (n+1)X4 binary arrays with every 2X2 subblock determinant equal to some horizontal or vertical neighbor 2X2 subblock determinant

76, 684, 4740, 35672, 260172, 1923780, 14150114, 104300522, 768160718, 5659345888, 41689048326, 307115065572, 2262407666898, 16666499139956, 122776828884698, 904459332925242, 6662871472736956, 49083319176509768

Offset

1,1

Comments

Column 3 of A185487

Links

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

Formula

Empirical: a(n)=11*a(n-1)-23*a(n-2)-69*a(n-3)+409*a(n-4)-768*a(n-5)-571*a(n-6)+4622*a(n-7)-5573*a(n-8)+1199*a(n-9)+2111*a(n-10)-8400*a(n-11)+12500*a(n-12)-4419*a(n-13)-490*a(n-14)+204*a(n-15)-1290*a(n-16)+1264*a(n-17)-1204*a(n-18)+320*a(n-19) for n>22

Example

Some solutions for 3X4
..0..1..0..1....0..0..0..0....1..0..0..0....0..0..1..1....0..0..1..1
..0..1..0..1....0..1..1..0....1..1..0..0....0..0..1..1....0..0..0..0
..0..1..0..0....0..0..1..1....0..1..0..1....0..1..1..0....1..0..0..1

Crossrefs

Sequence in context: A200167 A178262 A253411 * A007250 A137061 A230944

Adjacent sequences: A185478 A185479 A185480 * A185482 A185483 A185484

Keyword

nonn

Author

R. H. Hardin Jan 28 2011

Status

approved