A186920 Number of (n+1)X7 0..3 arrays with every 2X2 subblock trace equal to exactly one or two horizontal and vertical neighbor 2X2 subblock traces

1567936, 1613838400, 686342587904, 380882328583712, 193942830390429600

Offset

1,1

Comments

Column 6 of A186923

Links

Table of n, a(n) for n=1..5.

Example

Some solutions for 3X7
..0..0..0..2..2..0..1....0..0..0..2..2..1..0....0..1..0..2..1..2..0
..0..0..0..1..1..0..0....0..0..0..1..0..0..1....0..0..0..1..1..1..0
..0..0..0..1..2..1..0....0..0..0..1..0..0..0....0..0..0..1..2..3..3

Crossrefs

Sequence in context: A328563 A250517 A151620 * A185804 A252881 A183669

Adjacent sequences: A186917 A186918 A186919 * A186921 A186922 A186923

Keyword

nonn

Author

R. H. Hardin Feb 28 2011

Status

approved