A184767 Number of (n+1)X4 0..3 arrays with every 2X2 subblock singular

2248, 108496, 1967440, 62051344, 1444491280, 39939558160, 1005763454224, 26695990774288, 688562611427344, 18047210235975952, 468881159345732368, 12241663779855722512, 318750682398626741776, 8312086512859451766544

Offset

1,1

Comments

Column 3 of A184773

Links

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

Formula

Empirical: a(n)=36*a(n-1)-51*a(n-2)-7976*a(n-3)+65448*a(n-4)+105984*a(n-5)-2142720*a(n-6)+4230144*a(n-7)

Example

Some solutions for 3X4
..2..1..3..3....3..1..2..2....2..0..3..1....1..1..3..1....2..1..1..2
..0..0..0..0....0..0..0..0....1..0..0..0....0..0..0..0....0..0..0..0
..3..1..2..2....2..0..0..2....1..0..2..2....2..0..0..3....0..1..1..2

Crossrefs

Sequence in context: A250938 A230679 A236114 * A250160 A287701 A123297

Adjacent sequences: A184764 A184765 A184766 * A184768 A184769 A184770

Keyword

nonn

Author

R. H. Hardin Jan 21 2011

Status

approved